Error when trying to add observer

[Hanzanka]

File "/home/ville/.local/lib/python3.10/site-packages/weconnect/addressable.py", line 53, in addObserver
self.__observers.add((observer, flag, priority, onUpdateComplete))
AttributeError: 'filter' object has no attribute 'add'

I get this error when trying to add an observer to the climate requests. It works when adding an observer for the first time, but no longer works when I have removed the observer once before. idk if it is because the API or I have done something wrong.