The following is a list of issues you might encounter and what may have caused it:
Stock Level Discrepancy
You and the warehouse have different stock levels, depending on whether you have more or you have less than the warehouse will depend on how you investigate this.
If you have more stock then an order has not been confirmed delivered.
The warehouse have made an adjustment to stock, such as a stock loss.
Have you made an adjustment?
Was it correct?
Timing issues sometimes cause this to be a problem.
Finally compare stock movements with the warehouse.
If you have less stock.
You have confirmed a delivery when the warehouse have not despatched it.
This is quite dangerous as the warehouse could use different rotations and then you would have to perform adjustments.
You have made an adjustment which the warehouse have not.
Check the original receipt quantity if it agrees then check the stock movements with the warehouse.
Rotation/Product not found at Warehouse
You have a rotation on VC which the warehouse do not have.
You landed stock before the warehouse receipted it on their system
Check the receipt date of the stock
The stock has exhausted and you have not confirmed all deliveries or there was a stock loss
Check and compare the stock movements.
Unknown Product Code
The warehouse have a product code that you do not have.
Check the product at the warehouse.
Investigate why the stock managed to arrive and you had no product code setup as no code means no purchase order.
Unknown Rotation Number
The warehouse have a rotation number that you do not have.
Usually means stock has landed and not received on system.
Very common for re-landing and Returns to be missed on receipting.
It is Very Important as this stock is Duty Paid and it will be used on the first available orders.