Hi all

Wondering if anyone can help out a mechanically inept mtbr, I have recently been having a few issues with my chain slipping and partially slipping of my lower jockey wheel i think that the rear derailleur or jockey wheel has taken a hit and the spacing between the chain and the guide that holds the jockey wheel in place seems to have just enough gap for the chain to keep slipping. Is there a temporary fix for this or a way to close the gap enough to prevent further slippage?? Any advice is appreciated.
Cheers