Some clubs/schools might directly pay their NSO/PSO for their payment group registrations. This is how you can confirm they've been received.
1 - On your dashboard under payment groups, search for the club/school that sent you an offline payment
2 - Make sure that the billing contact and billing address are completed and refer to the submit payment section
3 - Select the method of online payment and the date when the payment was received and add a reference (eg : cheque number, receiver) and click on update payment information
4 - If you need to transfer part of the amount to the NSO/PSO for their portion, you can see the total breakdown by downloading the invoice