Attaching an entity of type 'X' failed because another entity of the same type already has the same primary key value

Question

ErrorMessage :

Attaching an entity of type \'FaridCRMData.Models.Customer\' failed because another entity of the same type already has the same prim

Answer 1

Try simple change state for entity wich you trying update and SaveChanges()

public bool Update(TEntity entity)
{

        context.Entry(entity).State = System.Data.EntityState.Modified;
        context.SaveChanges();
        return true;
}