Go to the Clients page

Go to the pencil menu for the client

Click on "View Client Details"

A slideout window will open

Click on the pencil next to "Client Details" under the green banner of the slideout window

Click on the fee schedule dropdown field

Select the desired fee schedule.

Click Save

Select "Current Cycle" if you want to update the fee to use new fee schedule or select "Next Cycle" if you want the new fee schedule assignment to be used in the future but not change the current cycle's fee.