iPhone device has been remotely deleted
My last iPhone was stolen and I blocked it. When this happened the person who stole it wanted to “sell” it to me and I refused (I live in Peru and these things happen all the time). Yesterday I got a phone call and one lady told me she was from apple support and that someone was trying to unblock my old iPhone, unfortunately I believed her and put my Apple ID and password on a link she provided, then I notice this was suspicious but it was too late. What I did is check my gmail account which is the one I use for my Apple ID and there were messages indicating my ID had been used in Canada. I changed my password immediately. Today when I woke up I find my new IPhone rebooted, as if new. When I checked my gmail account it said that they had erased my device. This process started the same minute this scammer contacted me. I am really distressed and I would like to know why they do this (to unblock my old iPhone) and most importantly how can I make sure my Apple ID is not being used by them.
iPhone XR, 12