E1: tem Ledger F4111 has item location BUT THE Item Branch Location F41021 is missing item locations

I have an item# / location that has good 'Item Ledger' transactions. Yet, on 'item branch/plant' 'location' for this item#, the 'location' is missing. We have 'item availability' for this item#. But, the 'item availability' for this 'item / location' is not showing up. Even if I 'check for zero' quantity, this 'item / location' is missing.

I believe the answer to this problem is to simply add the missing 'item branch' 'location' as a 'secondary' will fix my problem.

Please give me how to fix this problem.