Data reset period

When trying to activate data usage warnings, it has the wrong dates and won't allow me to change them. The billing period with my service provider is from the 27th through the 26th of every month

Hello Hollis,
We are sorry for the inconvenience. From your recent post, we are unclear of the issue. To assist you better, could you please elaborate on the same?
Thank you

Hello Hollis,
We are sorry for the inconvenience. From your recent post, we are unclear of the issue. To assist you better, could you please elaborate on the same?
Thank you