I quoted this guy 2-years old feature request https://requests.whmcs.com/topic/retrieve-invoice-currency
It was put to Under Consideration status for 2 years
This is very annoying. We build auto addon to check from the bank transactions then add payment to the invoice.
When call the API GetInvoice it does not include the currency information. So we need to call the GetInvoices and then compare one by one to get the currency information or need to call the GetClientsDetails to get the currency information.
Why don't just add currency information to the GetInvoice API?