Dynamics GP - Serial numbers are not available for selection, and the numbers cannot be used when attempting to adjust in

The numbers have already been used in the iv00200 table without proper receipt links

Find all records that are missing proper receipt links
select * from iv00200 where itemnmbr = 'myitemno' and RCTSEQNM <0

Delete the records from iv00200



Adjust the numbers back in using an inventory adjustment