Please check that Python API interface does it have writing to API implemented. Also try with curl does the api work at all. Also look at https://github.com/wekan/wekan at wekan/models/* is there some bug in API code.
Hey thanks. Well I found the error with the python api interface (https://github.com/wekan/wekan-python-api-client) it only uses POST and GET but I need PUT to change the card. With CURL it works just fine. I just have to edit my project now. thanks :)