After some tries I managed to solve the issue by deleting the entry for my network from kwallet. Deleting the password was not enough. Then I used knetworkmanager to connect to my network and kwallet furtheron remembered the correct key.
After some tries I managed to solve the issue by deleting the entry for my network from kwallet. Deleting the password was not enough. Then I used knetworkmanager to connect to my network and kwallet furtheron remembered the correct key.