Hi,

In standard Odoo 17/18, there is no "Proforma" state for credit notes. The only valid states are Draft, Posted, and Cancelled.

If you are seeing Proforma, it is coming from:

1. Customizations in your database (a developer or module added that state).
2. A third-party or OCA module that overrides invoice states.
3. Or a translation override that renamed "Draft" → "Proforma".

To fix this,

If it’s a real custom state added by code

• Check in Apps → Installed Modules if there is any addon related to invoices or refunds.
• Look inside the code for state = fields.Selection([... 'proforma' ...]).
• Remove or adapt it to follow Odoo’s standard flow (Draft → Posted).

Hope it helps