I seem to be going round in circles trying to unlock an old business phone I purchased from my employer from the O2 network. I requested an unlatch code which when I entered it gave the response "SIM network PIN blocked. Enter SIM Network PUK". I requested a PUK from O2 and entered it getting the response "Network unlock request unsuccessful". Same happened after I got a second PUK code from customer services. In the spirit of recycling not throwing it away can anybody help? It's a Samsung J5 if that helps.
It's hard locked due to too may failed unlock attempts.
You need an MCK from Samsung now.