Data usage reporting is incorrect

[trewdesarytdert]

I just switched to Telstra from Optus and my usage has apparently doubled since making the switch.

My usage habits have not changed yet Telstra reports double what I actually use.
I have Glasswire loaded to keep track of my data usage and it reports 9.1Gb's used last month yet Telstra advised I used 25Gb's in the last month.

Glasswire and Optus stats were spot on previously and based on that it seems Telstra's usage monitoring is incorrect.

How can this HUGE issue be resolved?

[cf4]

Have you checked the actual system data stats of your Tablet or phone. My online data meters and the device's system data meters have always been with in a few Megabytes of each other.