This might happen when the license expired before uploading it. Open the license file (it's a normal text file), and check expiration on it. Otherwise - try restarting the server, and then upload again.
If nothing works - Please check the logs for errors regarding license, and share so we can look.
I am having this same issue. I can't seem to get any help anywhere to get another license file either.
The log message related to license key is as follows...
"2020-09-04 08:54:26.0285 info [POST] "/license/upload" 200 2.064315ms (source: /home/circleci/.go_workspace/src/github.com/demisto/server/web/middleware.go:90)"
Attached is a screen shot of the license screen.
MattEllisPAC20, are you not able to perform any action? When the system is downgraded to Free Edition - you should be able to work with it, under the Free Edition limitations (https://start.paloaltonetworks.com/rs/531-OCS-018/images/Cortex_XSOAR_Community_Edition_FAQ.pdf)
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