Business continuity issue for client - Free plan not upgraded despite making payment

Business continuity issue for client - Free plan not upgraded despite making payment

We had mapped a client to our Zoho Store account, and made a payment on their behalf for 1 year Standard plan for Zoho Books. It was showing us that the client is now on a Standard Plan, however, our client has reported that they are still on Free Plan. This has impacted their business, as they are not able to generate new invoices for new clients. This is not done, as payment has been made, and service is not provided. We seek an urgent solution for this issue.