Thanks for your response Tut.
I found it under “General Ledger account” - Account name - contains “Suspense”.
As for the why:
I’m working with a company where person A is reponsible for payments to suppliers and making sure all purchase invoices are sent to person B who handles the finances in manager.io
To check that purchase invoices are received, transactions stay in the suspense account until the invoice of that purchase is received. At the end of a period Person B sends Person A a report of the purchases missing an invoice (purchase transactions still in the suspense account).