How can you dictate to someone who they will vote for in a general election based on their registration.
That’s contrary to the American principles of secret ballot.
This is why changing the nominating process from the convention run by the party to a primary system open to the electorate was a horrible idea. The party can not control who their nominee is in an open primary.
Basically, if the party you want to vote for in the general election is not holding a primary, then you won't be voting in a primary election. There is no constitutional right to vote in a primary election.