one x help

[syclone fan]

Hey guys new to the forum. Searched all over but can't find an answer. Love this phone but after its last update its been so weird. Chrome locking up, SIM card errors, freezing, weird bugs etc. Recently it won't receive mms from a certain contact. Whether it be kik, alternative sms apps or the stock one. It gets them fine from others but not her. She says they send and her friends get pics but idk why mine won't! I have mobile data on and WiFi, and 6 gigs of data which I barely touch. Sorry for the rant lol