Perhaps take a look at this:

In Odoo's supporting documentation it says:

By default, payments in Odoo do not create journal entries, but they can easily be configured to create journal entries using outstanding accounts.

• An outstanding receipts account is where incoming payments are posted until they are linked with incoming bank transactions.
• An outstanding payments account is where outgoing payments are posted until they are linked with outgoing bank transactions.

These accounts are usually of type Current Assets and Current Liabilities

Payments that are registered in Odoo are posted to the outstanding receipts and outstanding accounts until they are reconciled. At any moment, the outstanding receipts account’s balance in the general ledger shows the balance of registered incoming payments that have not yet been reconciled, and the outstanding payments account’s balance in the general ledger shows the balance of registered outgoing payments that have not yet been reconciled.

I found that while it says "These accounts are usually of type Current Assets and Current Liabilities" (which makes sense, that I had to set the outstanding payments to Current Assets for it to show up in the dropdown on the default settings (and an AI query seemed to endorse this).

Hopefully this will lead you to resolve your problem.