Double check the beneficiary's bank details against the details in the payment confirmation and make sure they match. If they are correct, then your beneficiary will need to follow up with their bank.
[Check] To help avoid payment delays, always reference your payments clearly and pass the reference details onto the beneficiary so they know to look for it.
However, if the bank details are incorrect, then please contact support to arrange a trace to attempt to locate the funds. Please note this will only be done on a "best endeavours" basis. This will incur a fee (please refer to your contract). A Trace can only be completed against Priority Payments (SWIFT), the option to locate Local transfers is not available.