Data Usage Charges when i have Unlimited Data

I have had the Unlimited Data Plan for the past 5-6 Months. But every month that i go over 1024 GB i get usage warnings. I contact support when i get them to let them know i'm getting data usage warnings even though i have Unlimited Data but they just assure me that i will not be charged and to just ignore the warnings. But every month i go over i get charged for it.

I had $70 added this month for data usage but on the same statement it shows $49.99 for unlimited data. Then i have to contact support and they just say they will credit me but it won't show until next month. It's very annoying and frustrating. This is the 3rd time it has happened. I tried to explain to support that i think something is wrong with my account or with the automatic system that charges for data overages but they just say " i assure you this will not happen again" but it has and i'm sure it will. I don't want to have to go through this process every month i go over 1024 GB.