iPhone screen not working

my iPhone is not letting me open any apps and when someone calls me it rings but does not how who is calling and will not let me answer. a few days ago it said I was going to get a virus and get hacked so I calle apple support and they fixed it but shortly after that my password changed and I was locked out for a day. before I could call again it changed back and I was able to get in and it worked perfectly fine up until yesterday when my screen was not letting my click any apps.