WMS - Available Whse Qty out of sync with Available Inv Qty

prototyper

We have a number of items that have less in the bin contents than on inventory. I'm not too sure how this has come about.

Our main problem is that Picks will not autofill. This is because the bins have less than the available inventory which is fully reserved.
We have attempted to post a whse. item journal to bring the bins inline with the inventory but the net effect is the same as the calculation of available warehouse qty is including postings to the adjustment bin. Do we have our adjustment bin setup incorrectly or are we missing a step.
Any help appreciated.