Purchase order status BUG

as you can see here the DRAFT filter is totally messed up . after fetching the code I knew the problem was the status itself not the filter .the completed items has the status Draft , docstatus 1 and per_billed 100%. I changed nothing in the code . it’s a bug tested in 5 servers. I think it’s a thing with the change status code; some purchases are not doing what they are suppose to do , but I never found it .