Prevent members from booking if they don't have booking credits

This validation rule prevent members without any money credit to book resources. Contacts can still book resources with or without credit.

This rule doesn't check if members have enough money credits to cover the price of their booking.

It is simply a way to ensure they have some money credit (above 0) in their account before letting them book.

Log in to dashboard.nexudus.com if you aren't already.
Click Settings > Validation rules.
Click Add rule.
Click on Manual entry.
Name your validation rule.
Add a Description for your rule to let other admins know what it does at a glance.
Toggle on This rule is active.
Select Bookings in the Record type drop-down list.
Add the Error message to display if the validation rule is not met.
Add the following code snippet to the Formula field.

isLoggedIn = false OR record.Coworker.IsContact() OR BookingCreditAmount(record.Coworker) > 0

Click the Save Changes button.

All set! Your validation rule is now active. You can test it by trying to book as a member without any money credit. If the rule works, you should receive the error message you defined.