Campaign Error - Completed Bug

Hi Guys,

I‘ve just started playing Diablo IV with my friend. We immadietely played together on a Server. After a small Break - the Server disconnected and once we looged back on his main Story campaign was still there while mine Said that I have Already played the full campaign and hence will not receive any XP etc. This of course completly wrong - I am only lvl 18 and did Not Even finish the First act

I have alredy (I) deleted and reinstalled the game, (ii) created new Charakters and relogged back on the original one, (iii) changed difficulty levels

I am not sure what Else to do - can you please help?