Replace the wall dimmer switch with an on off switch.
Can you put a ceiling fan on a dimmer switch.
The new switch does require an additional electrical wire.
In this circumstance the light kit could be connected to a dimmer switch and the fan motor connected to a toggle switch.
You cannot use a dimmer switch on a fan motor but you can find fan speed controllers.
The wall dimmer switch reduces power flow and interferes with the fan control.
A broken ceiling fan motor and a house fire are obviously not ideal outcomes however there is some good news.
A dimmer switch as the name suggests lets you control the intensity of the light produced from the light to which it is connected such as a ceiling fan with a built in lighting fixture.
An example of this is that the motor in your fan could be damaged and rendered useless.
You may need an electrician for this.