The only solution is a single national primary, held on the same day (or perhaps over the course of a weekend) using ranked choice voting.
So I've never been able to get a clear answer on this: why can't we operate the primaries like General Election Day?
I've never understood this either, the way we do it feels childish, almost treating the presidential selection process like some game or sport and not with the professionalism and seriousness it desesrves. It also deprives a good half of the country of any say more often than not as it's usually down to one candidate by the time it gets to some of the later states.