Hello Susan Warren, 

Please try this solution and see if it will fit your business needs:

Disable the option Allow booking below minimum capacity:  in Amelia -> Settings -> Appointments settings and then access your database. In your database you need to find and open the wp-options table, and find the option amelia_settings in it. Then please edit this option and when you find property 'appointments:' there you need to change the option
openedBookingAfterMin from false to true like here:

"appointments": {      
        "isGloballyBusySlot": false,        
        "openedBookingAfterMin": true
    }

Let me know if this helped.

Great, glad to see that. Thank you for letting me know. 

You are welcome. 

If you have any other questions or concerns feel free to open a new ticket and we will gladly help.

Hello Susan, 

Could you please tell me have you set this to true 

"openedBookingAfterMin": true

and enabled the Minimum setting in Amelia -> Appointments -> Setting? 

And people can book for less than the minimum in this case?

If this is true, then your use case can't be achieved with Amelia's built-in features, unfortunately.