Go to the Calendar and click settings (on the app it's in the top right corner).
In the Pricing tab, scroll all the way down to Additional Charges.
You can just put zero for cleaning. If you need to increase your nightly rate to make up for this, scroll all the way back up to Minimum Nightly Price.
Did @Shelley159's answer below enable you to turn off the cleaning fee?
If so, it's always a lovely gesture to mark a top answer ☑️. It's like a big virtual hug to the members who supported you and the best answer also supports other Hosts who may have similar questions in the future. 😊