Full signal bars but nothing loads? Work through these 10 checks in order — from the 10-second fixes that solve most cases to the deeper resets.
Mobile data ON
The toggle gets switched off by accident more than anyone admits.
Data Roaming ON (abroad)
Required for travel eSIMs — it won't add charges to a prepaid plan.
Right line selected for data
With dual SIM, exactly one line carries data. Make sure it is the right one.
Check that mobile data is actually on
iPhone: Settings → Cellular → Cellular Data ON. Android: Settings → Connections (or Network & internet) → Mobile data ON. The Control Center / Quick Settings toggle gets hit by accident more often than anyone admits.
Airplane Mode: on for 10 seconds, then off
If it was on, that was your answer. If it was off, toggling it anyway forces the phone to re-register with the network from scratch — this alone fixes a surprising share of stuck-data cases.
Traveling? Turn Data Roaming ON for the travel line
The #1 cause abroad. iPhone: Settings → Cellular → tap the travel eSIM → Data Roaming ON. Android: Mobile networks → Data roaming ON for that SIM. Costs nothing extra on a prepaid travel eSIM — keep roaming OFF on your home SIM instead.
Dual SIM: check which line handles data
With two SIMs active, exactly one carries data. iPhone: Settings → Cellular → Cellular Data → pick the line with the data plan. Android: SIM manager → Mobile data. A travel eSIM that is installed but not selected looks "active" and delivers nothing.
Wrong network — select it manually
Phones pick networks automatically and sometimes camp on one your plan does not support, especially abroad — and they will not switch back on their own. Turn off automatic network selection and pick a supported network (full steps in our network guide below).
Manual network selection guideOut of data? Check the plan balance
A depleted or expired plan looks identical to broken settings: full bars, no data. Check remaining data in your provider dashboard or app — eSIMfly customers see live usage and expiry under My eSIMs.
Low Data Mode / Data Saver quietly throttling
iPhone: Settings → Cellular → your line → Low Data Mode OFF. Android: Settings → Network & internet → Data Saver OFF. These block background traffic and can make apps look offline.
Turn the VPN off and test
A VPN that cannot reach its server blocks ALL traffic. Disable it, test data, then reconnect. In some countries VPN endpoints are blocked entirely — always test with it off before blaming the connection.
Check APN settings (mostly Android)
If a plan needs a specific APN and the phone did not pick it up, data stays dead. Android: Settings → Connections → Mobile networks → Access Point Names. eSIMfly plans provision the APN automatically. If you ever need the exact value, ask our support - it is not included in your installation email.
Restart — then reset network settings
Restart first. Still dead? iPhone: Settings → General → Transfer or Reset iPhone → Reset → Reset Network Settings. Android: System → Reset options. Saved Wi-Fi passwords are cleared. On Android, that reset screen may offer an "Erase eSIMs" or "Erase downloaded SIMs" checkbox - leave it UNTICKED, or you will delete the eSIM itself.
Traveling with an eSIM?
Nearly every "data dead on arrival" case is steps 3 and 4 — roaming off, or the wrong data line. If data worked and then died mid-trip, it's usually step 5: the phone hopped to an unsupported network and stayed there.
eSIMfly customers: your dashboard diagnoses this automatically — open My eSIMs and any detected issue shows a step-by-step fix for your exact situation.
eSIMfly customer? Contact us at support@esimfly.net or on WhatsApp with your order details and location — we can see your eSIM's live connection status and tell you exactly what's wrong.
Signal bars show a voice connection to a tower, not a working data session. The usual culprits: mobile data is switched off, Data Roaming is off while traveling, the wrong SIM/eSIM is selected as the data line, or the phone camped on a network your plan does not support. Work through those four checks first - they solve most cases.
Two settings cause most abroad-only failures: Data Roaming must be ON for the line you use abroad (for travel eSIMs this is required and does not cost extra - the plan is prepaid), and the phone may have auto-connected to a local network your plan does not include, which needs manual network selection to fix.
No. A travel eSIM connects to local partner networks, which the phone technically treats as roaming - but the data you use comes out of the plan you already paid for. Data Roaming ON is a requirement for travel eSIMs, not a cost risk. It's your HOME carrier's roaming that creates surprise bills, so keep roaming OFF on your home line and ON on the travel eSIM.
Toggle Airplane Mode on for 10 seconds and off again to force a fresh network registration, then restart the phone. If it still fails, reset network settings (Settings > General > Transfer or Reset > Reset > Reset Network Settings on iPhone; System > Reset options on Android) - this clears corrupted network state but keeps your eSIMs installed. Then contact your provider's support with your location and what you tried.