Not able to export to AME at all

I have never had this issue before but now I cannot export a scene from CA to AME. 

I am using a Mac Mini M1 with 16GB of memory.

I have used a similar puppet before - it is 17mb photoshop file. The animation is not complex. The stage is quite big 2000x3000px and it a transparent background but I tried adding a green screen and it still did not work. I then downloaded Chloe and made a test scene with her but it would not export.

There is no error message in AME, I just see the programme trying to encode the file but no thumbnail. I left it for 7 hours to see if anything happened but still the same thing in the morning. There is a file in the save point with 1mb of information.

I tried uninstalling and then reinstalling CA and interestingly, Chloe test scene worked but then once I tried to export my other scene, it would no longer work, back to square one. Not sure what to do, whether this is a compatibility issue with the M1 chip but I have exported clips before.