Problem with Customer Exit MGA00001 ( Enhancement for MM01 )

Dear SAPGurus ,

I have implemented Exit MGA00001 for making validation while maintaining Profit Centre when a Material is created based on Plant.

I am maintaining Plant and Profit Centre linking in ZTABLE .

Everything is working fine while the user tries to maintain Profit Centre in the view Costing 1 of MM01.

But when the User maintains Profit Centre in the view Sales: General/Plant ( without maintaining in Costing 1 view )as shown below :

An error alert is coming with no message like shown below and the user is not allowed to proceed.

I have checked for any earlier enhancements made on MM01 . But failed to find out the reason for the same.