I think we've tried everyting, reinstalling Hamachi, macOS, complete reformat and reinstall of OS and Hamachi, paid accounts, free accounts, etc.
I've tried to find a corrolation to the type of networking setup and/or intenet connection, but no luck, it rains on the just and unjust alike. It does seem less likely to affect new Mac hardware and new macOS', but that's imperical so far, most of our installs are pre-2018 Mac minis, many of which can't run Mojave.