How to solve the error with robokassa?

Question

opencart

Invalid parameter: InvoiceID opencart robokassa Site on opencart 2.3, help solve the problem
here is the site home-textiles24.ru

Answer 1

This is the answer that came up. Can you tell me where to fix it?
This error occurs on the side of the store. At the time of the formation of the request to initialize the payment, you pass us the InvId value, which has already been used before. This parameter must take a unique value with each redirection to the ROBOKASSA service. The error shows that one of the customers has already paid for this order number earlier, and now you are redirecting another payer to us, issuing him the same invoice number. Correct the moment by changing the value of the InvId parameter.

Answer 2

See where InvId is passed and how it is formed.
From the name, the Order number with or without a prefix should be transferred there. In any case, it is unique.