I set up the average hotel pricing manually but it does not display as intended on the hotel page. How to fix that?

You should turn OFF the Set auto calculation average price options on Hotel > All hotels > Hotel Price.

If it is turned on, the system will automatically calculate the average price based on the room rates, and your manual input will be ignored. In this case, you should turn off the “Set auto calculation average price” option, so that your manual input will be used instead.