Default voicemail greeting changes

i try to post all the scary issues I have with my iPhones in this forum but always get blocked from Apple but trying again. My phones are hacked and cloned, I’m sorry I’m not a criminal hacker or coder/programmer, so I’m not sure the technical term but someone is physically inside my phones like mimicking me. My phones have never been in anyone else’s possession nor are the jail broken which is a new term for me I learned from the interne. But that’s neither here nor there, new issue and Apple will say ask your carrier, which I did, my carrier is AT&T and the answer is I’m changing it somehow. Anyway, if you call my phone and voicemail picks up, at least yesterday, the first time it answers it will be a male voice, and my voicemail is the default greeting, it will be a British or something close to that accent, and I’m in the US and I’ve never heard that before. Second time you call my phone it’ll be the normal default grading, which is a female voice with an American accent I guess you would say. I called a third time and it was another default, normal greeting, but a different phone number thats not mine. And then I just gave up and called AT&T who informed me that I must be changing it I said for her to call twice and she did the same thing happened. She heard the British one and the American one but again she’s like the only thing we have is that it has to be you changing it. OK I asked her how I change the default greeting then, she can’t explain it. It’s exhausting. The lack of knowledge that any of these people have I certainly don’t have it but I know more than them when they tell me my voicemail default greeting I’m changing that’s not possible. Point is has anyone had this problem? And if so, how did you fix it and that’s just one of several major issues with my phones.