No signal after landing

Nine times out of ten this is a settings issue, not a network issue. Work through the list:

1. 1The eSIM line is turned on in your SIM list.
2. 2Data Roaming is ON for the eSIM line. This is required, and it is safe, your plan is prepaid.
3. 3The eSIM is selected as your mobile data line, not your home SIM.
4. 4Toggle Airplane Mode on and off, or restart the phone, to force a fresh network search.
5. 5Still stuck? Select the network manually in cellular settings, and on Android check the APN (a few countries need it set by hand, the exact value is shown with your eSIM in the app).