My iPhone is not responding after I downloaded a third party app

Hi so I downloaded a app called Match To Win Real Money Games and when I opened it it gave a option if I want them to send notifications and when I trieWhen I tried to answer it I couldn’t so I turned my screen off And then when I opened it the thing that says if I want to turn notifications of that off or on is still there and I can’t touch my phone it’s unresponsive when I tried to switch it off they asked for passcode which I couldn’t entered bcuz my phone is unresponsive

[Re-Titled by Moderator]