Short answer
After arrival, check a few phone settings so the eSIM can connect to the local network.
Checklist
Turn Wi-Fi off temporarily to test mobile data.
Make sure the eSIM line is turned ON.
Set the eSIM as the line for Mobile Data / Cellular Data.
Turn Data Roaming ON for the eSIM.
Keep your main SIM for calls if needed, but keep roaming off on the main SIM if you want to avoid roaming charges.
If there is still no connection
Contact support with:
your current country/city;
a screenshot of the SIM/eSIM list;
a screenshot showing the eSIM selected for Mobile Data;
a screenshot showing Data Roaming ON.