Weird man answers my phone

In August last year, my phone began to act weird. My boyfriend would call, but my phone would not ring. Instead, a man would pick up the phone and begin to ask questions in a firm, monotone voice. He would say things along the line of, “Who is calling?” and “What is your reason for calling?” If my boyfriend answered the man or spoke back, the phone line would go silent. It was weird, but I ignored it as no one else mentioned it and it was happening frequently enough that he knew to just hang up and call me again and again until the call would actually go through to me. As creepy as it was, I assumed it was some new AI voicemail feature that wasn’t working properly.

It became an issue when, about a month later, my mum called me in a panic (she was tracking my uber which had gone off course,) and got through to the man. Given these two things happen ring at once, she jumped to believing i had been kidnapped and started yelling at the man while threatening to call the police if the phone wasn’t handed back to me. I can’t remember exactly what she told me the man had said to her, but it had a bit more detail than what my boyfriend had previously described. Eventually, I saw my phone ringing, noticed about 10 missed call notifications, and picked up the phone to my mother mid panic attack. She was hysterical, asking if I had been kidnapped and if I’m okay. I calmed her down and explained that i asked the uber to drive off corse, and that my boyfriend has heard the man on the phone before but i thought it would just go away. Once she was okay, I hung up after promising to get the issue sorted.

The next day, we spent hours researching the man. We literally couldn’t find anything. The closest we got was someone whose phone had been hacked to redirect calls, but my boyfriend and mum were firm that the voice was not human, as it was too “AI-like,” and it also hadn’t asked for any personal details other than why they were calling and who they were (so I had no reason to believe this was someone calling to gather personal information).

Fast forward to today, I had long forgotten about the man and no one had mentioned it for a while. I was out with a friend and when we got separated, she tried to call me. As you’ve guessed, the man picked up. She was freaked out and assumed someone had picked up my phone from the ground, and when she called back again just to hear the man’s voice again, she also believed i may be in trouble. She luckily saw me and ran over, asking who the hell that was and if i had my phone. I pulled my phone out of my front pocket, where I swear i did not feel it ring, and saw two missed calls. She was a bit shaken, and I explained this had happened last year but stopped. Now I’m worried this is going to start again.

On the way home, we spent the next hour calling my phone. It would ring like normal and send her to my voicemail. We tried different settings (my phone is usually on dnd) sleep mode, ringer on, ringer off. We could not intentionally get through to the man after trying for a full hour.

I have been calling my own phone using other peoples mobiles all day. I cannot get through to the man. I sat down with my boyfriend once he got back from a trip, and he told me the man has been back for a little under a month whenever he tried to call. Not only this, but he told me that it seems to be a different man each time, and has started saying things he didn’t before. He instantly pulled out his phone to call and show me, which as expected just went to regular voicemail.

Could anyone please tell me what I need to do to stop this? Should I get a new number, or do I need to replace my phone? I don’t want people getting freaked out when they call me, especially my poor mum. Any help would be very much appreciated, the faster the better, as I really don’t want this to become an issue again.