I just encountered this issue with my wife's new Iphone 14 pro we purchased today and needless to say it is quite annoying so I'm going to summarize the experience, problem and solution briefly (as I understand it) so that others may not have to be bothered by this as much as we are.
What happened: My wife said it was time to upgrade her phone so we went and bought an iphone 14 pro for her because I like mine. We buy the phone for full price and walk out with the new phone and her old phone because they only would give her 20 bucks for it. We assume we can set it up and transfer the data ourselves since Verizon wants to charge 30 bucks for that after we just dropped over 11 hundred on a new phone with no discount. The sales guy gives us a vague description of what to do and does not even turn the new phone on.
The problem: We take the new phone home and start a phone to phone transfer thinking we just saved 30 bucks because I knew how to do this from my phone (i got mine 6 months ago roughly). The phone gets to the point of updating ios and then just hangs on the install for 2 hours then I try again and it hangs again. Then again but there is no progress bar or anything to indicate its doing anything.... By holding down the power button on the 14 pro you can select start over so I tried it too many times before getting smart and accepting it wasn't going to work.
Finally I go into the new phone with my wifes apple ID (do not restore anything just go in with the apple id and password). Once I get into the phone I go in and realize the new phone is 1 ios update behind the old phone. I update the new phone to the same ios. I reset the phone (erase all data and settings but NOT THE ESIM!). This now loops me back into the new phone as if I had just brought it home but running the same IOS version as the old phone.
THE SOLUTION: NOW that I have both the old and new phone running the same IOS; phone to phone transfer works perfectly.
Why might this be happening. I think the most logical explanation is that verizon got the shipment of phones before a new IOS came out and Verizon does not want to train their people on how to get around this issue so they train 1 person in the store and charge for his time to update phones for apple. Maybe apple will have a rep at verizon soon I dont know. The sales guy vaguely mentioned I might have to update the phone before I can do a phone to phone transfer but he could not give me detailed instruction on how to get into the new phone without restoring anything and then how to wipe it without deleting the esim.
By the way, this is the very last question when you are resetting the phone at the bottom of settings/general). It does not confirm your choice so make sure you dont delete the esim as this might complicate thing further!
We bough the phone at 3pm and its now 11pm. My wife thinks her phone is defective and does not want to use it, and I'm secretly celebrating my win...
Its all bad BUT I HOPE THIS HELPS YOU ALL
Summery: If you buy a new phone you need to make sure its on the same version of IOS as the old one to do a phone to phone transfer. I believe an icloud restore gets around the issue but most people are doing phone to phone because they are out of space on their icloud. In any case, to update the new phone you have to go past all the restore stuff and just log in using the apple id and password. It might not even need to be the id of the person using the phone but I didn't try this. Then go into the setting of the new phone and update it to the version your old device is using. I see a ton of potential issues here with older devices not being able to go far enough and new devices being upgrade past the point your old device can go accidentally as apple give you the option to skip over updates but not go back...
Here we are. Once you have matched the IOS versions phone to phone transfer will work after you reset your new phone again (NOT THE ESIM) because this then loops you back into the new phone where phone to phone transfer gets prompted. THEN you can fully update and setup the new phone and leave the old one behind. It is also wise to turn off cellular on the old phone if your going to use it like a mini ipad or music player or something. The battery will last longer and the devise will work better with that turned off.