Hi R Brahmankar - Thank you so much for your reply.
When I was following up on the solution you provided, I saw that the 261 actually looks for the assembly material in unrestricted stock and my assembly is actually lying as a sales order stock.
I then moved the material from sales order stock to unrestricted so that my production order could be confirmed.
Secondly, 531 pushes the component materials back into unrestricted stock, but since these components are parts of the assembly belonging to the customer, is there is a way I can trigger a 261 E, and receive the components via 531 E.?
thanks again.
Regards,
Vivek