Unable to complete data transfer

[RTM31]

Just received my new iPhone 13 Pro.  Trying to activate and sync to old phone by following prompts.  Gets through some of the process, but then I get an "Unable to Complete Data Transfer" message and it asks me to reset the 13 to factory settings and start over.

I powered off and back on the current 7 Plus, then hit the reset button on the 13.  It reset after several minutes and I ran the process again with the same result.  Anyone having similar problems or can provide any guidance?

[RTM31]

Is it possible the original phone 7+ needs to be plugged in or charged beyond a certain point?

[mama23dogs]

Make sure both are full charged, and updated to current iOS.  
Are you using the phone to phone transfer as prompted by your new phone?

The camera captures the blue nebula, and you just set the phones close to transfer data.  Unless your new phone has far less storage, it should work beautifully.