Hi CU12061712-0,
Item model groups shouldn't be changed with existing open transactions and on-hand inventory for the product. The Item model group is directly proportional to tracking the inventory of the product and does impact components like unit costs and dimensions associated with the product/item.
Reasons for not being able to see the transaction:
1. The link between the InventTransID and the Product Id with reference to the Item Model Group Id is broken.
2. The link between on-hand inventory used to track the stock of the product and the associated open transactions is broken.
If there are no open transactions associated with the new Item model then would recommend you to do the following:
1. Through a X++ script go ahead and close the open inventory transactions associated with the old Item Model group. Also, check for the product dimensions, storage and tracking dimensions associated with the product.
2. Once the new item model groups are added, check the on-hand inventory after adding the new item model group.
Hope this helps. Happy to answer questions, if any.
