If you contributed to the work and are a rightsholder, then the situation could be that your co-author has received the full payment for the work and is required to on-pay other rightsholders, such as you.
In that case, you will need to speak to your co-author about the payment, and if you are not sure of the correct percentage you should receive, please check your contract or contact your publisher.
If you would like to check or change your payment preference for allocations to your works, contact our Member Services Manager, Rosie Daniele. However, if your co-author wishes to continue to receive the payments and on-pay to you, you should discuss that with them.