If a parent states when they register it has an error message saying "You do not have any matching payment plans to choose from. Please contact your organization administrator to complete registration."
How to troubleshoot
Go to Programs -> Program Registration -> you can narrow the search for finding the player's registration by using the filters.
Check the age and gender of the player's registration.
Go to your program which the player is registering for -> then click on Registration Fees
Check to see if the age and gender of which the player is, attached to any fee on the registration fees page.