Saving plan data for a given Master Data

I am trying to save data using Manual Layout using Planning Folder. In my manual layout I have selected one of the characteristic in Data Columns and assigned one of the master records as default value. Once the data is saved I don't see the transaction data saved for default master data value in layout but gets saved under # (not assigned) master data.

Any ideas what may prevent data getting saved under correct master data record?

Any help is highly appecriated.

PS: This error is not noticed in Development and QA environment.

Regards,

Sachin