Cannot login to UMC after updating to 4.2-3 errata284

The login fail and I am presented with this error.

Internal server error.
The server encountered an unexpected condition which prevented it from fulfilling the request.
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/cherrypy/_cprequest.py", line 670, in respond
    response.body = self.handler()
  File "/usr/lib/python2.7/dist-packages/cherrypy/lib/encoding.py", line 217, in __call__
    self.body = self.oldhandler(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/cherrypy/_cpdispatch.py", line 61, in __call__
    return self.callable(*self.args, **self.kwargs)
  File "/usr/sbin/univention-management-console-web-server", line 1161, in index
    return acs(binding, message, relay_state)
  File "/usr/sbin/univention-management-console-web-server", line 1171, in attribute_consuming_service
    response = self.acs(message, binding)
  File "/usr/sbin/univention-management-console-web-server", line 1288, in acs
    response = self.sp.parse_authn_request_response(message, binding, self.outstanding_queries)
  File "/usr/lib/python2.7/dist-packages/saml2/client_base.py", line 580, in parse_authn_request_response
    binding, **kwargs)
  File "/usr/lib/python2.7/dist-packages/saml2/entity.py", line 1087, in _parse_response
    response = response.verify(keys)
  File "/usr/lib/python2.7/dist-packages/saml2/response.py", line 975, in verify
    if self.parse_assertion(keys):
  File "/usr/lib/python2.7/dist-packages/saml2/response.py", line 895, in parse_assertion
    if not self._assertion(assertion, False):
  File "/usr/lib/python2.7/dist-packages/saml2/response.py", line 780, in _assertion
    if not self.condition_ok():
  File "/usr/lib/python2.7/dist-packages/saml2/response.py", line 575, in condition_ok
    conditions.not_on_or_after, self.timeslack)
  File "/usr/lib/python2.7/dist-packages/saml2/validate.py", line 86, in validate_on_or_after
    (nooa, now))
Exception: Can't use it, it's too old 1518468954 > 1518469719

Hey,

please try clearing your browser cache and deleting all existing cookies. Then try logging in again.

Please also try logging in without using SAML. The URL for that is https://your.server.name/univention/login/

Also: have you rebooted after the upgrade?

Kind regards,
mosu

Yes I rebooted after update.
The error corrected it self overnight for some reason.

Thanks for the prompt ansver.