"PDP Authentication Failure" error: the fix
This intimidatingly named error has a concrete cause: the phone cannot authenticate at the network's data gateway (the APN). It is fixed in settings, without deleting anything.
What it means
PDP is the data session your phone opens with the network. If authentication fails, you have signal but no internet. It is almost always a wrong APN or an old network setting interfering.
The fix, in order
- Check the plan's APN: your provider lists it in the installation e-mail. On iPhone: Settings → Cellular → (eSIM line) → Cellular Data Network. Type the APN exactly, no spaces, and leave username/password empty unless instructed.
- Data roaming ON for that line.
- Airplane mode for 10 seconds.
- Full restart.
- If it persists: Reset network settings (Settings → General → Transfer or Reset → Reset → Network Settings). It wipes saved Wi-Fi networks but does not touch your data or the eSIM.
If the error comes and goes
It can be a congested local network or the phone hopping between carriers. Try manual network selection with another carrier in the country. The interactive eSIM Rescue guide covers this case for your phone brand.
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See my price →Frequently asked questions
What is the APN?
The access point that connects the phone to the network's internet. With eSIMs it usually configures itself; this error means it needs a manual check.
Does resetting network settings delete my eSIM?
No. It wipes saved Wi-Fi networks and network settings, but installed eSIM profiles remain.
Is the PDP error my phone's fault or the eSIM's?
Usually the configuration (APN) or the local network at that moment. Neither the device nor the eSIM is damaged.
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