In order to un-register the items on the return, first an inventory adjustment needs to be created for the 4 tires that are going to be un-registered. Then, you will be able to un-register the tires and delete the Return. Please see below the steps for un-registering and deleting after the inventory adjustment journal has been posted.  



I tested on DM creating an inventory journal and then un-registering the items on the Return and I was able to complete the transaction. Please see steps below.

 

  1. Go to Inventory adjustment and add 4 tires to the specified item. Click Post.

 

  1. Go to the Return Order, check the Auto Create box and then click Post all.

 

 

  1. Note that the status of the line changed from Registered to Expected. At this point you may delete the order.