Credit memo request for a variant material in sales order has overall status blocked and Unable to create a billing document

Hello Everyone,

I  created a credit memo request for an Invoice with variant material/ Configured material. Credit memo request is created but overall status is BLOCKED. I am not unable to create the billing document for this Credit memo.

I received the following Error during billing document creation.

003000XXXX 000010 "Create billing document" not allowed (Sys. status Cost, object VB003000XXXX000010).

Any suggestions on it are appreciated.

Regards,

Rakesh.