What this means
This is almost always a Square linking issue.
For credits to apply:
The rate must be properly linked to a Square item
If the receipt says “Custom Amount”, the rate is not linked correctly.
Credits cannot apply to Custom Amount charges.
How to fix it
Go to Rates
Confirm each rate is linked to a Square item
Avoid using Custom Amount for bookable rates
Best practice:
All rates should always be connected to Square items.