Bought iphone 5s and it's previous owner removed icloud account on it.
I created my own icloud account and associated with it.
Everything is ok, but when i insert a sim card, it requres me OLD icloud credentials (one which was used by previous owner).
If i enter my own credentials it says : "this account could not be used to activate phone".
If i remove sim, turn phone on, and enter my credentials it works fine.
What could i do ? (rather than contacting old owner who is remote)
I'm not searching for any illegal (ticks or hacks) about bypassing Icloud.