This error message means that your account did not accept the GDPR and got locked after some time. It c*ually be 'fixed' by the following steps:

1. Make a new character in another server

2. Fill in the GDPR information (age and country, it should pop up automatically to be filled in)

3. Accept the GDPR Policy by clicking the 'Cog' in the top right in-game, then click 'Data Transfer Outside EEA' and then click on 'Accept'

4. Wait 10-15 minutes

5. You should now be able to log back onto your old character and continue playing

If step two doesn't appear, proceed to step 3, make sure you accept. If you're accepting, on a new character on the same account / login that the error appears (accept the GDPR on server 2 when you play on server 1, for example), and it isn't working, contact customer support in game.