When a fan will not turn at full speed the first step is to look at the speed indication on the fan controller. Is the top LED illuminated when pressing the top of the fan speed bar multiple times?
If the LED will move to the highest position:
The issue is between the fan controller and the motor. If the fan is controlled by a pull chain the most likely issue is the fan must be set to in the high position. Once the fan is set to high it is recommended to no longer use the pull chain. For additional troubleshooting steps consult the article "Will My Ceiling Fan Work With The DW4SF Fan Speed Controller?"
If the LED will not move to the top position:
This issue is likely that the Max Level in the app was lowered from the high position. This may be desirable if a fan wobbles at high speed.
To check the app setting start by pressing the the dots ':" on the fan icon:
Choose Device Settings:
Choose Advanced Settings:
Scroll down to Range options and confirm the Maximum Level is set to Max:
