Hi
@bor.casado 1.Make sure that you have roaming enabled.
To enable data roaming you would normally go to Settings -> Network & Internet -> Mobile Network -> SIM1 or SIM2 (depending which you want data);
Enable "Roaming" toggle.
Please note this may incur data cost charges.
2.Also make sure you are on the latest firmware update.
3.Some users with this same issue have perform a reset and it has seem to solve it.( keep in mind to back up your data before factory reset)
If after all this you keep encountering the same issue you should reach out to your phone operator to check if is something on their end