Hi,
So months ago I purchased an Instagram account offsite but now the previous owner is trying to hack it. He does forget password, then clicks “need more help logging in” and it gives him the option to choose the old phone number which was attached to this account which obviously is his number. I have 2fa on, login requests on and all types of security on, but he managed to turn off 2fa and change the number without logging in. How can I delete that number? Please help!