If your eSIM shows no service or no internet abroad, the fix in roughly 9 out of 10 cases is one switch: Data Roaming must be ON for the travel eSIM line. On iPhone: Settings > Cellular > [your eSIM] > Data Roaming. On Android: Settings > Network & internet > SIMs > [your eSIM] > Roaming. Travelers switch roaming off out of habit — years of horror stories about roaming bills trained us to. But a travel eSIM works by roaming: it connects to local networks as a visiting line by design, and the rate you were quoted already assumes that. If roaming is on and you are still offline, work down this checklist in order — it is sequenced from most-likely to least-likely cause, and steps 1 through 4 resolve the large majority of cases without touching anything technical.
The 10 fixes, in order
- Turn Data Roaming ON for the eSIM line
- Set the eSIM as your Mobile Data line
- Toggle Airplane Mode for 10 seconds
- Restart the phone
- Select a network manually
- Check or reset the APN
- Wait out network registration (up to 15 minutes)
- Check your balance — $0 means no data
- Do NOT delete and reinstall the profile
- Contact support with the right details
1. Turn Data Roaming ON for the eSIM line
This is the single most common cause of a "dead" travel eSIM, which is why it is fix number one. Crucially, roaming is a per-line setting: enabling it for your home SIM does nothing for the eSIM. On iPhone, go to Settings > Cellular, tap the travel eSIM specifically, and switch on Data Roaming. On Android, open Settings > Network & internet > SIMs, pick the eSIM, and enable Roaming (Samsung: Settings > Connections > Mobile networks > Data roaming). Leave roaming off on your home SIM if you want to be certain it never bills you — the two settings are independent.
2. Set the eSIM as your Mobile Data line
With two active lines, the phone routes data through whichever one is selected — and if that is still your home SIM, the eSIM sits idle while your phone tries (and fails, or expensively succeeds) to use the wrong line. On iPhone: Settings > Cellular > Cellular Data and select the travel eSIM. On Android: Settings > Network & internet > SIMs > Mobile data (or "Preferred SIM for data"). Keep your home SIM enabled for calls and texts if you need bank SMS codes abroad — just not for data.
3. Toggle Airplane Mode for 10 seconds
Airplane Mode forces the modem to drop and re-register on the network — a soft reset of the radio without rebooting. Switch it on, count to ten, switch it off, and give the phone a minute to reattach. This clears a surprising number of stuck states, especially right after landing when the phone latched onto a network before you changed any settings.
4. Restart the phone
A full power cycle goes one step deeper than Airplane Mode: it reloads the modem firmware and re-reads every installed SIM profile. If you installed the eSIM at home and it never touched a live network before your trip, a restart on arrival is often the moment everything clicks into place. Thirty seconds, no data lost, fixes more than it has any right to.
5. Select a network manually
Sometimes the phone auto-attaches to a local network that rejects the connection, then stubbornly refuses to try another. Force its hand: on iPhone, Settings > Cellular > [eSIM] > Network Selection, switch off Automatic, and wait for the list of local operators. On Android: Settings > Network & internet > SIMs > [eSIM] > Automatically select network — off. With a multi-network travel eSIM, pick any operator on the list; if the first refuses to register, try the next. Once you are online, you can switch back to automatic.
6. Check or reset the APN
The APN (Access Point Name) tells the network how to route your data. On virtually all modern travel eSIMs the APN is auto-provisioned when you install the profile — you should never need to type one in. iPhones apply it automatically and, on most carrier profiles, do not even expose manual APN fields. Android is where problems appear: manufacturer skins (Samsung, Xiaomi, Oppo in particular) occasionally fail to apply the pushed APN, leaving you with full signal bars but zero data. Check Settings > Network & internet > SIMs > [eSIM] > Access Point Names: if the list is empty or a stale entry is selected, add the APN exactly as your provider specifies — Roamzy users can find it on the eSIM detail page in the dashboard, or ask support. Never copy an APN from a random forum; a wrong APN produces exactly the symptom you are trying to fix. Signal but no data is its own beast — we cover it in depth in eSIM connected but no internet.
7. Wait out network registration
When your eSIM meets a foreign network for the first time, the local operator has to verify the roaming agreement and register your device — and that handshake is not instant. A few minutes is normal; after landing at a major hub, or after crossing a land border into a new country, it can occasionally stretch to 10–15 minutes. If you have done fixes 1–5 correctly, put the phone down and give it a quarter of an hour before escalating. Impatient profile-deleting during this window (see fix 9) is how a temporary delay becomes a real problem.
8. Check your balance
Obvious in hindsight, invisible in the moment: a pay-per-MB eSIM with a $0 balance behaves exactly like a broken one. There is no package to "expire mid-trip," but if you have used up your balance, data stops until you top up. Check your balance on your Roamzy dashboard (over Wi-Fi if the eSIM is your only connection) and top up with USDT or USDC — it typically credits within minutes, and whatever you add never expires, so overfunding costs you nothing. If you are unsure how fast you burn through data, see how much data you actually need.
9. Do NOT delete and reinstall the profile
This is the one fix on every generic troubleshooting list that can make things permanently worse, which is why it is here as a warning rather than a step. Most eSIM QR codes — including Roamzy's — are single-use. Deleting the profile from your phone does not "reset" anything on the network side; it consumes the installation, and scanning the same QR again will fail. If you genuinely suspect a corrupted profile (rare), contact support first and ask for a reissued installation before you delete anything. Two minutes of asking beats being stranded with a dead QR code.
10. Contact support with the right details
If nothing above worked, hand it to a human — but hand it over well. One message containing all of the following gets you a fix dramatically faster than "my eSIM doesn't work": your phone model and OS version, the country and city you are in, whether the eSIM line shows signal bars, "No Service," or "SOS", which of fixes 1–8 you already tried, and the network name shown (or the operators listed under manual selection). Roamzy support runs on Telegram at t.me/roamzy_support_bot, and common answers live on the FAQ page. Since Roamzy is data-only with per-MB metering, there are no plan tiers or validity windows to debug — it is almost always device settings, network registration, or balance.
Still stuck? Device-specific quirks
A few failure modes cluster around specific devices, as of 2026:
- iPhone — carrier settings update: go to
Settings > General > Aboutand wait 30 seconds; if an update prompt appears, accept it, then restart. Stale carrier settings can block registration on networks the profile otherwise supports. Full walkthrough in our iPhone eSIM guide. - iPhone — Low Data Mode and VPNs:
Settings > Cellular > [eSIM] > Data Mode > Low Data Modecan throttle background connectivity, and a VPN profile that only worked on your home network can silently blackhole all traffic. Disable both while troubleshooting. - Samsung / Xiaomi / Oppo — APN not applied: the most common Android-specific failure; see fix 6. On these skins, also confirm the eSIM is actually toggled on in the SIM manager — some models disable a line after a software update.
- Older or carrier-locked phones: a phone locked to your home carrier will refuse any third-party eSIM, and some models sold in certain regions ship without eSIM support at all. Verify yours against our eSIM-compatible phones list before assuming the profile is at fault.
- 5G handshake issues: on some networks, forcing
4G/LTEinstead of5G Auto(in the eSIM's network settings) stabilizes a connection that keeps dropping.
And if the eSIM never showed any signal from the moment you installed it — at home or abroad — that is a different diagnosis tree: start with eSIM shows no service after install. For the full setup-from-scratch path on either platform, our Android guide and general guides cover every screen.
FAQ
Why does my travel eSIM need Data Roaming turned on?
Because a travel eSIM is technically a foreign line visiting the local network — that is roaming, by definition. The setting only gates whether the line may use data outside its home network; it does not change what you pay. Your price is set by your eSIM provider, and with per-MB metering you pay only for bytes actually used.
My eSIM has full signal bars but no internet. What is wrong?
Signal bars mean the radio registered; no data means the data session is failing. In order of likelihood: mobile data is routed to the wrong line (fix 2), the APN was not applied (fix 6), or your balance is at $0 (fix 8). See the dedicated guide to connected but no internet.
Can I just delete the eSIM and scan the QR code again?
Usually not — most eSIM QR codes are single-use, so deleting the profile burns the installation and a re-scan will fail. Contact support before deleting anything; a reissued installation solves it cleanly, deleting first solves nothing.
How long should I wait after landing before assuming something is broken?
Give it up to 15 minutes with Data Roaming on and the eSIM set as your data line. First-time registration on a foreign network involves a roaming-agreement handshake that is sometimes slow at busy airports and land borders. Most phones connect within a couple of minutes.
Does my eSIM stop working if I did not use it for a while?
A package-based eSIM often does — validity windows expire whether you used the data or not. A metered eSIM like Roamzy has no validity window: the balance never expires, so an eSIM you installed months ago works the moment you land, as long as the balance is above zero.