Billing document( T code:VF01) number range interval error

Hi Guru,

While Creating Billing document i.e (VF01) I got an error. But apart from that I already maintain the Number range Interval in FBN1 as well as SNUM. But that number ranges I assigned in Billing document type also. Then also facing the same error.

So please give me some solution Asap

Regards,

Sukdev.