Question regarding email (police mater, England)

Hello everyone,

I was invited to a voluntary interview with a police officer, during the interview it was explained to me that a person had been receiving emails (threatening) from an account that after an I.p check links to my old WhatsApp that has a picture of me. The email was also linked to my old mobile phone number. I also must add that I do know the person.

Now I was completely taken a back by this because as far as I was aware for my number to be linked to a gmail, the text to set the account up would have had to go to my number?

How can this even be possible? The fact that I know the person too, my god, I didn’t even know what to say bar I have no idea.

I’m not tech savvy but I can do the basics and even I cannot think of how someone could have done that?

I asked if he could not just trace the I.p location to find the exact location and he shook his head.

I do have a solicitor and they did come with me but he was very young and didn’t advise much.

I’m trying to just make sense of it in my head, thanks for any help.