Condition 0006 is only defined for customers

Dear All,

I have generated and inter company invoice. For this Intercompany invoice one IDOC also generate but its not getting posted.

While taking list of ot posted IDOCs from BD87 this document is laying with the status 51 (Application document not posted). And its showing the error " Condition 0006 is only defined for customers"

Please suggest me

Regards,

Abhinesh