How to solve violation of primary key cannot insert duplicate

Question

I am trying to insert value from code in which i want talukcode = regioncode like 

model.talukcode = model.regioncode;

previously it was like

 model.villagecode = MaxValue + 1;

but now i am trying

model.talukcode = model.regioncode;

and i am getting an error 

System.Data.SqlClient.SqlException: Violation of PRIMARY KEY constraint 'PK_ppatalukmaster'. Cannot insert duplicate key in object 'dbo.ppatalukmaster'. The duplicate key value is (3, 3).
The statement has been terminated.

Is there any way to solve this error through code.