Hotpoint First Edition non-freezer is constantly freezing ice?

Hotpoint fridge 1st edition with no fridge box and is not meant to freeze is freezing.
I switched it off one night to de-ice as it has no de-ice button since it is not meant to freeze. Within 24 hours of switching on ice had formed again inside of it.
I have noticed a small gap in the rubber that seems to have been bent which would allow some air in am unsure how to straighten the rubber so it is fully sealing. Any help would be appreciated