Just in case, you can find how Active Hours are calculated here.
The total active hour is greater than the usage hours of your app because it takes into account more parameter.
First, there is a Idle Timeout : If no one use your application, it will wait X before being inactive.
Then, the scaling setting you configured will also play role in increasing the active hour.
It may not be related to your issue but just in case you did not know, it is worth mentioning.
If you have a pro plan, you can also contact pro support.