TRansfer Order - Negative stock figures

Dear Friends:

Using T.code LT03, I entered Warehouse no,plant,delivery and pressed enter

In storage, I selected 003(open storage) and selected post

In movement data, I entered the data

source storage type: 003 (open storage)

source storage section - 001 (Total section)

storage bin - 16-03-69 and pressed enter

I get the error ' Storage type 003 does not allow negative stock figures'.

How to overcome the error?Please advise.

Thanks&Regards

MSReddy