"You can only use one foreign currency per transaction." error when syncing with QuickBooks online.

The sync error "Business Validation Error: You can only use one foreign currency per transaction." is a result of incorrect GL Account configuration. Read on to learn how to prevent this error.

Error    Invoice    Error creating QB invoice from Acctivate a7549071-342e-494e-aa2f-13ac698b2304 (123456): BadRequest. Details: Business Validation Error: You can only use one foreign currency per transaction. 

This error typically indicates that the GL accounts associated with a transaction may be configured incorrectly. It can occur when an invoice includes one or more line items using a currency other than the company's home currency.

Income and COGS accounts in QuickBooks must always be in the company's home currency, while other account types, such as assets or liabilities, can be in a foreign currency. If a GL account in a foreign currency is mapped to an Acctivate sales or COGS account field, this mismatch can trigger the error.

To prevent this, ensure that only sales/income accounts and COGS/expense accounts are mapped to Acctivate’s income and COGS account fields.

To resolve the error, update the mapped income and COGS accounts to use the correct account types, void the invoice, and then reattempt invoicing. If needed, toggle the field mapped to the income and COGS accounts, such as the Product Class or Branch field, before retrying. This should prevent currency mismatches and allow the transaction to process correctly.