Some accounting categories in Xero are system-controlled and exist only for internal accounting logic, such as bank revaluations. These accounts appear in the Chart of Accounts but can’t be used on bills because allowing manual postings would break Xero’s automated calculations. This restriction is intentional and cannot be overridden.
When you try to sync a bill with such an accounting category to Xero, the sync will fail and Request Finance will display an error to you. To resolve this, please select a different accounting category.