I need to delete all transactions & operations in Odoo Online V18.

Initially I installed only the purchasing app and uploaded all my products and PO's. Later I installed the inventory app, it allowed me to track inventory.

However, it wouldn't let me allow 'Track Inventory' on items that where already Billed & PO'd.

Went to delete the Bill's and the PO's, but it wont let me because they are received.

Then went to delete the receipts but it wont allow me, I can only Return the item.

So I Returned them and now it wont let me delete them either.

In short, I want to delete all Deliveries, all Receipts and all Bills, so I can start tracking stock.