When someone is "jumping your case", it means that they are being critical of you or confronting you about something. There are several synonyms for this phrase, including "nagging", "harping on", "pestering", "hounding", and "harassing". Other alternative phrases that convey a similar meaning include "getting on someone's nerves", "rubbing someone the wrong way", and "pushing someone's buttons". Whatever words you use to describe this behavior, it is important to remember to communicate respectfully and seek to resolve any conflicts or issues in a constructive manner.