Link to Helpdesk Article: http://success.rallynow.io/support/solutions/articles/69000088745-connect-your-lawpay-account

To Enable Automatically Emailed Receipts
Navigate to https://secure.lawpay.com/ and login with your LawPay credentials
Select your name in the top right
Select "Developers"
Ensure the following toggles say "On"

Click "Save Changes" at the bottom of the screen