Why isn’t my customer added to the Customers module after I receive their payment?
Customers are added to the Customers module in Zoho Payments only when their card is saved in any Zoho Finance application (such as Zoho Books, Zoho Invoice, Zoho Checkout, Zoho Inventory, Zoho Commerce, or Zoho Billing).
Insight: Card or bank details are saved when you request payment information, add them manually in your Zoho Finance app, or when your customer saves them during invoice payments.
If the customer makes a one-time payment, and there’s no saved card, a customer profile will not be added to the Customers module in Zoho Payments. However, the payment they made will still be recorded in the Payments module.