Item Type Keyword Attribute

I have a number of items been in FBA for a couple of months but are now stranded for ‘Inventory Error’ normally this rights itself but on these it hasnt.

Running them through the why is my ASIN not displaying help tool brings up the following:

Your listings ASIN is missing the ‘Item Type Keyword’ attribute.

• Go to Manage Inventory to edit your listing, then click the ‘More Details’ tab to edit your ‘Item Type Keyword’.

Anyone know what this means as there isnt an ‘Item Type Keyword’ option in the more details tab?