I will answer your questions as best as I can. I am obviously not tech savvy, so bear with me here on questions. I'll tell you what i know about the phone as my friend told me. She lives in a seniors community, and there is a lot of sharing of this and that, and one day my friend found the phone in its original box with a charger, and a note saying "good phone, just needs a sim card". My friend took the phone to her carrier to switch her old phone to the one I am speaking of here the Samsung Galaxy A12. The carrier said the phone was fully unlocked, and the only problem they could find was that when they made a regular phone call, they could not end the call unless they forced a shut down on the telephone. She told me about it, and she gave me the phone. Since I've had the phone I did do a factory reset on the phone, and this morning I connected it to my mobile hotspot and updated all the apps on the phone through the google playstore. Since there is currently no sim card in the phone, I thought I would try to install messenger (being non tech savvy) and see if I could place a call through messenger. There was no problems placing the call to my current cell phone, which is an android also, the A12 dialed through on messenger to my cell phone no problem. I didn't answer it I just tried to disconnect from the call by pressing the hang up button on the A12. It did not hang up. I had to reject the call on my end to stop the A12 from ringing my phone. Since then I have turned off permissions as was suggested, and done all that was suggested on the thread Nothing changed. I also tried safe mode, and as you know, or I found out, apps that were not pre installed do not work in safe mode. I have an older phone than the A12 and was hoping to use the A12 phone for my everyday. However if it will not place a call, and I can't get it fixed, I don't want to use it. I thought there was possibly a way to fix the issue. I hope this helps. It's all I know. Thank you for taking time to respond.