Error: The field address must be a string and array type with maximum lenth of 50 in ASP.Net MVC

dear sir i am new in asp.net mvc in my table column address which is nvarchar(50) when string have much lenth then there is error messsage "The field address must be a string and array type with maximum lenth of 50"

after i update my table address to nvarchar(MAX)

rebuild and again updateing and inserting the record i am getting this error while i set my addres column to nvarchar(Max)