Customer owned stock in S42022 feature

[AAkash1]

Hi, 

I am running Customer stock process in S42022.

I am creating a purchase order with C , and creating delivery but I am not getting Usage B in EWM and also the owner is the plant, which should be the customer. And when I do a GR , queue is getting stuck and I get a message 

Enter a customer for special stock B

Message No. M7072

Diagnosis

You did not enter a customer for the customer-related special stock B.

Any clue If I am missing anything?