Good chance the hinge is goosed, you'll need to open it to work out the size to order a new one. Whilst you're at it, replace the other side too.
OK so this looks promising Thanks!
Thats were I'd be heading, unscrew one of your hinges and take it with you to screwfix to make sure the new one will fit.
@Quincy started
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Good chance the hinge is goosed, you'll need to open it to work out the size to order a new one. Whilst you're at it, replace the other side too.