MSSQ-SQBWE exceeded by xxx

Hi

I have created a Stock transport order for Project Stock from Plant A to plant B

I then created a delivery against this STO

I Then did a Goods issue against this delivery

Then I tried doing Goods receipt against the out boun Delivery  in Plant B

I get the following error message

MSSQ-SQBWE exceeded by XXX qty : Mat code Plant B sloc ofPlant B Q.

Please do advice on this error an how to go about resolving the same