A big problem with my iphone 12

hello! yesterday when i turned off my iphone 12 (prod.red) the apple logo popped up and turned on intermittently. So I put on recovery mode and it said to connect the phone to the computer with support.apple.com.

I connected the phone to iTunes to perform the update but after doing the 6.5gb download it said "software extraction" and then after finishing even this upload in the phone the apple came back on intermittently and so in the iTunes app an error appeared. It's like a loop what can I do? I've already tried recovery but nothing there either, I've also tried external apps to get out of recovery like dr.phone or something else but nothing. I've also tried the key combinations up fast, down fast and sideways but nothing (when I hold down the sideways key in this combination the screen goes black and if I leave it it goes back to recovery)