Error executing hook activate-changes #1: need more than 1 value to unpack

Traceback (most recent call last):
  File "/omd/sites/sldc/local/share/check_mk/web/htdocs/wato.py", line 9954, in call_hooks
    hk(*args)
  File "/omd/sites/sldc/local/share/check_mk/web/plugins/wato/auth.py", line 192, in
    api.register_hook('activate-changes', lambda x: create_auth_file(load_users()))
  File "/omd/sites/sldc/local/share/check_mk/web/htdocs/wato.py", line 7135, in load_users
    id, password = line.strip().split(":")[:2]
ValueError: need more than 1 value to unpack