Phone Issue or FreePBX

I’ve been successfully running 16 lines on an internal only network. but about a week ago (30 days later). Some of my phones came up with the error below. They are all Avaya 1120e. I saw that it was a TLS configuration issue, but does anyone have tips on how to fix this. I’m not sure if it is freepbx or specific to the phones.

Could no obtain license. Login has been denied

I’ve not come across these phones at all but looking at the message it looks like a phone issues as FreePBX doesn’t licenses number of extensions. It could be that the phone is encountering an error connecting to the FreePBX system and giving out an incorrect error message.