PMS cannot reconnect to plex account

Server Version#: 1.26.0.5715
Player Version#:

PMS lost all connection to all device after update
reinstall but no connect reaction
need a way to reconnect PMS ans account

First verify that PMS is up and running.

Browse to http://<IP_OF_QNAP>:32400/identity

Then show us the output

Secondly, please confirm, that both your QNAP and your workstation is on the same IP Net, and that the IP Net is in Private Address Space