Everything was working just fine
I know I am very late, but I want to give contribution too. This error is really strange, because the browser is not able to understand how the changes should be rendered because the classes and their properties might have changed but not committed to the database.
So do one thing,
create one migration in Package Manager Console(Tools > NuGet Package Manager > Package Manager Console) using this command:
add-migration UpdateMigration
where UpdateMigration is the name of your Migration. You can give it any name of your choice but please be specific.
After that, we just need to update the database, so run this:
update-database
Now that you have committed your changes to the database, just refresh your browser and there you go!
Hope this helps.