Facebook can't change name/number

Whenever I tried to change the name of my Facebook account, it trigger(checkpoint) phone verification or ask "call fb friends to recover".

I can't do phone verification, because I have no access, and I can't even change the phone number to my source, because it also trigger same verification.

It's happening from last 2 month, I know it happens because the device is not same. But from whom I bought the accounts it also not helping me.

So is there any way so that Facebook recognize my device and allowed me to change account name/number easily.

If you bought your accounts they probably took it back to sell it again.. Can't see any other reason.

The seller should have given you that information when you bought the accounts. Or at least let you change it. Talk to the seller again and discuss how you could change the details. Otherwise, you have to live with it until the accounts are resold to someone else.

Do you see other options like logging in from another IP ?

Have you tried with old IP ?