App Builds and AI2 Companion - Neither working, even with older projects and checkpoints

All projects appear to load but they do not appear on the Companion it just shows the opening screeni.e. MIT App Inventor 2 followed by the type in the 6-character code etc.

On the broweser the under Connect the AI Companion, Emulator and USB are greyed out whereas the Refresh Companion Screen, Reset Connection, Hard Reset etc. are usable.

I have tried using both the latest browser version and previous version

Built: August 18 2024 Version: nb198
Use Companion: Use Companion: 2.72 or 2.72u

The companion is version 2.72u

I have tried loading many older projects going back months and some over a year.

If I create anew blank project it does work!

I have tried building the apps and downloading them and whilst they do install they do not run properly. As an example a project that I have been working on for many months now crashes with the following message:

Clear cache for Light?

Lights closed because this app has a bug. Try cleaning the apps cache first, and then reopen the app

Obviously I have tried this but it doesn't change anything.

These appshave been working for many months and no changes have been made to them.

I have reverted back to the Classic setting but no change there either

The Android devices are version 14, one is a Pixel 8a and the other a samsung tablet and they were both working fine until yesterday

Interesingly I have just tried the blank app again but inported an extension and now that does the same i.e. doesn't draw the blank screen, just leaves the opening Companionon screen!!