Value difference in the on hand form and inventsum table..

Hi, All.

While trying to post transfer journal to move particular item from one warhouse to another i got  below error.

1.00 cannot be picked because only 0.00 is/are available from the inventory.

Then i checked the on hand form and it shows that available quantity is 30.00.

then i checked the inventsum table it has no value in availphysical column for that particular item.

how it is happening that form has values but not in the table.

Because of that i cannot post the journal.

Suggest the way to solve issue or find the root cause