Data Contract changed without notice

Somehow my data contract was changed. Not sure when or why, but the contract I have and the subscription you bill me for (same price though) is not the same. I have an MTN made for Home 120Gb contract used by my elderly mother to keep in contact, but now only have night time,e express and youtube data (yipeee!!). Please fix your admin!!! If not incorrectly billed, you mess up my data - one way or another you keep messing up my life....PLEASE STOP and FIX THIS NOW!!!