MacBook Pro A1502 internal OWC Aura SSD Mac OS issues

I have an 13” MacBook Pro (A1502, beginning 2015) which I want to hand over to my son. I had installed an OWC Aura SSD as the internal drive with Catalina on it which worked perfectly fine as my boot drive. However, I erased and have tried to install a fresh copy of Catalina (and newer compatible Mac OS’ses) but I can’t get it to work.

I have read multiple stories on the forums but I can’t understand what is causing this. I have contacted OWC for help as well. The fact that it originally worked means it should be possible to get it to boot.

I have tried these things:

• Erasing the drive with the correct GUID partion map. It shows me a volume and the drive

• Downloading Catalina (with the right link) directly from Apple

• Installed Catalina on a bootable USB stick and started up from it and tried installing it from there

I get stuck, after I fill in my iCloud details and then I get the message that ‘the software is not available’ or something like that, even though I have the installer files and so on, copied to the bootable USB stick. Which boots fine.

I think it has something to do with the partioning map or something like that. Who knows how to solve this? And it is possible, I had it working perfectly fine until recently.

Many thanks!