PLEX no longer plays when I click the Play button

Plex Media Server
1

Server Version#: 1.22.0.4163?
Player Version#: 1.22.0.4163? – aren’t these the same?

Plex worked fine for a year or so.
This week it stopped playing Plex movies, and local movies and TV shows from our library.

And every time I log in on a browser to watch anything I now get a pop up message:

(!) Invalid Credentials
Your credentials have expired. Please sign in again.
[ignore] [OK]

If I click either Ignore or Okay Plex is still there sometimes and nothing plays.
Other times the page refreshes and I have to log in again.
As soon as I login again I get that message WHAT THE FISH?

How can I watch movies again with Plex?

Thank god when you buy Plex they give you peer to peer support instead of them supporting it. I mean why would a company support a product you pay for?

2

IDENTICAL PROBLEM (or so it seems). Unsure if this coincides with an update, but suddenly I continue getting the “Invalid Credentials: Your credentials have expired. Please sign in again.” When I do, play buttons don’t work. It’s like Plex becomes a bunch of static pages. When nothing I tried worked, I uninstalled Chrome, and reinstalled. Plex again worked fine for several days, then suddenly without warning “Invalid Credentials: Your credentials have expired. Please sign in again.” When I do, play buttons don’t work.

Plex Version 1.22.0.4163
Windows 10 (64)
Chrome Version 89.0.4389.90 (Official Build) (64-bit)

(I use The plex app on multiple devices - android - fire stick - roku - ipad - and all work fine. The Plex server computer is also working fine)