Failed to Activate Device

This is a brand new MacBook Air and I migrated my older computer to this one which is a Mac studio and in doing so I developed some crazy extension problems every time the computer booted up programs wouldn't work things of that nature tried to fix them I couldn't so I said I'm going to erase the hard drive and start over. I erased the hard drive and now it won't activate. Spent hours on the phone with Apple as they were trying to help me and they couldn't help me either now I got to send a brand new computer back to them so they can revive it. Too much control these days shouldn't have to activate it till after you install the software I don't get it. Thank you for your time though and your answer I appreciate it !!! And I have no idea if activation lock was on or off never even got that far. The computer isn't even listed in iCloud for me so I don't understand....