Hello @sparviero799 ,
Welcome back to the Poly Community.
CMA is end of life for a while now so I can only suggest to upgrade to a current solution like RPRM or PDMS-E or even Lens.
Other people found the same issue and posted >here<
Please ensure to provide some feedback if this reply has helped you so other users can profit from your experience.
We had the same issue with one of our RPAD's that was scheduled for upgrade and we didn't get to it on-time. A cheat for getting access back into the interface is the change the date on your computer clock. We rolled a PC back to a date in November and we were able to load flash again. Not a great long term solution but it allowed us to get access to the interface to run the upgrade.