Hi Rahul,
I ran the flow in my test environment and was able to auto generate the batch number successfully. Maybe by means of sharing my config/steps you will be able to proceed.

Figure 1. Batch number group config

Figure 2. Released product - batch number group specification

Figure 3. Storage dimension group config that is used for item "Batch"

Figure 4. Tracking dimension group config that is used for item "Batch"

Figure 5. PO creation - no location has been specified since I would like that everything will be controlled by the RECV on the warehouse form and after this the configured location directives
After a load has been created the user starts with defining the packing structure

Figure 6. Packing structure [Batch ID already auto-generated]

Figure 7. LP receiving

Figure 8. On-hand
Thanks,
Alice