I am writing also here, maybe someone from the staff will see this post. This bug was reported also via ticket game support.
Since last Easter event 2020, the first line from the companions inventory is full. Therefore I can not change anymore the companion with a different one. I tried different browsers both laptop and smartphone (Android base) and is not working.
Because I am not the only one who's having this problem, I hope that someone will invest some time to solve this bug.
Adrian D - Sv3 RO