I am unable to connect to 4G and I have used 4G and 4G+ before I bought my new terminal.

Do you know how i can connect and use this service, i have checked the bandwidths in Spain and it is available?

i have tried to add it manually but maybe i did something wrong and i have tried to search for it automatically too.

i have another Blackview terminal A9 Pro, an inferior model and it connects automatically without and issues.

Hi there.
The Blackview S8 is supposed to work with Spanish phone carriers.

I suggest to perform a factory reset and try again. If you still can't connect to any networks, it means that the phone is, unfortunately, faulty. In this case you'll have to contact your seller to have it replaced under warranty.

4g is working fine for me (Orange España).
If you have Orange I can share the APN I use with you.