Hi Reynaldo,
If you cant see the WPUUMS idocs(i believe you are using aggregated sales idoc from POSDM to ECC), please check the below
1.Go to /POSDW/AGGR and find the Aggregate number for the store/posting date combination(with relevant min and max date)
2.Check the status of the aggregate number
If the status is "5" the aggregation is completed(which means you should be able to see the idoc in WE02 for the relevant store).
**It will be worthwhile checking the partner profile settings in WE20 wherein partner type KU should have the store number configured as customer with all the relevant message types(especially WPUUMS in your case) in POSDM outbound message section.Similar settings should have been done in ECC in the inbound message section.
If the Aggregate status is not "5" then you need to analyse depending on the status.You may have to either run the /posdw/odis to create an idoc if its not created at all.
Hope it helps.
Best Regards,
Aram.