Error Psychopy x EyeLink subsequent Calibration

Dear PsychoPy Community,

I am encountering an error subsequent to the calibration and validation with the EyeLink 1000. I am receiving the following error message:

Error in ioSever.shutdown():
Traceback (most recent call last):
File “C:\Users\Klin Psy\AppData\Local\Programs\PsychoPy\lib\site-packages\psychopy\iohub\server.py”, line 1012, in shutdown
del self._hookManager
AttributeError: _hookManager
displayAPI: init_net() start use_tcp_only=0
displayAPI: Connecting
################ Experiment ended with exit code 1 [pid:11064] ##################

I am not sure why this error occurs, because the experiment runs smoothly after restarting. Any help would be highly appreciated.

Thank you very much in advance and all the best

Celina Müller