Data transfer issues

I recently got iPhone 12 Pro, and was trying to transfer data and apps from my old iPhone XR to the newer one. I tried all possible options

1. Phone to Phone data transfer (Fails when about 4 min is left stating the error ' Move device closer to continue', while they are connected to power and lying next to each other)
2. Restoring from iCloud (fails stating that ' Restoring from iCloud failed')
3. Using mac, I backed up my old iPhone and I tried restoring that backup on newer one and it goes all the way to the end and pops an error of 'Restoration is not completed, Please restart to continue', after restarting it tries to sync and then the I have to restore to factory settings'

Tried this over 10 times now, tried restarting all my apple devices but nothing fixed. A four hour call with Apple Support was in vain too......

Can't really think what to do other than replacing the device itself or cancel my purchase and stop the trade-in that I initiated. Any help would be appreciated!