The camera is locked, the lights blink and I've tried all the batterie

Recently there was an error in my camera because the black film got stuck

The battery was low and I still took the photo The film got stuck because there was possibly a power failure for the camera to work

I pulled the film very hard and managed to remove it, I removed the rest through the back door and the camera was apparently normal

I bought new AA alkaline batteries like the ones I already used But the camera starts flashing lights as soon as I put them on and remains locked without taking pictures . I already opened it to see if there was anything broken, apparently fine

How to fix it? :(