Start with the simple checks
Confirm that the travel eSIM is turned on, selected for mobile data, and allowed to use data roaming when the provider requires it. Also check that airplane mode is off and that the phone has joined a supported network.
What an APN does
The APN tells the device how to reach the mobile data service. Some profiles install the correct value automatically. Others provide a specific APN in their installation instructions.
Do not invent an APN
If the supplier gives an APN, enter it exactly as provided. If no APN is supplied and automatic settings are already present, changing random values can make troubleshooting harder.
Line on → travel eSIM selected for data → roaming setting checked → restart or airplane-mode cycle → network selection → APN only if required by the package instructions.
Still no data?
Save screenshots of the eSIM line settings and network status before deleting anything. Deleting an installed eSIM can make recovery harder because some QR profiles are single-use.