Movement type 101 is not allowed while doing IBD for STO

Hi Gurus,

While doing Inbound delivery from VL31N for an Intra company STO (The supplying and receiving plants used in the STO is of same company code), I am facing this error "Movement type 101 is not allowed".

While OBD, PGI was done succesful.

I have searched the scn.sap a number of times but unable to find solution of this issue.

The PO document type is copy of UB and item category is U.

Any clue on why this error is coming?

Thanks,

Kiran