@Kim5182
The base price is a price used for all dates on the calender. It can be a fixed amount or it can be "Smart Pricing", which varies the price between two limits. The price for a specific date or a specific time periode can be changed by setting the price for that date or time period directly into the calender (custom price).
So i have some questions:
1. Are you not able to change the base price setting or can't you change (customize) a price directly into the calender ?
2. Are you performing those changes on the multicalender (""professional hosting tools" needed) or on the listing calender ?
3. If using the app, did you you also try to make the changes on the website (using a desktop/laptop) ?
If you make a price change, is there an error showing or is the change simply not executed/saved ?
(I hope Airbnb support have asked these questions also).