iPhone 8 been hacked
Hi, my phone has started: sending messages, making phone calls, sending photos and making group chats on instagram.
It is also sending random messages on snapchat, as well as opening random apps.
I have signed out and changed the password to my apple ID, as well as changing snapchat and instagram passwords. When I change my Apple ID password, it says that someone from an elsewhere location is accessing it, so I clicked don't allow (however I am unsure if it has actually stopped them as at least twice the same message appeared). I also have a MacBook which I have also disconnected my Apple ID from.
Please can anyone help me as to what to do next.
Thank you
iPhone 8