the cupboard plate/jam that the door closes against has a crack in the area that the hinge is mounted to.it probably split when improper size screws were used or from over tightening the screws.One of the screws that fasten the hinge to the plate will not tighten/stripped.My question is can i reinforce the cupboard plate/jam to mount the hinge properly?
Check the other doors. Often there are blanking covers on the sides not used by the hinges. Depending on your layout, you may get away with swapping doors over.
Failing that, I have seen repairs of this nature made using epoxy resin.
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix cabinets and cupboards.