Sometime zerotier cannot connect each device

I have been using zerotier service for a long time. During this week zerotier cannot connect each device. I set zerotier in 5 PC. They connected properly last week. But this week maxOS PC cannot connect each other for example 3 PC windows OS connect properly without disruption and 2 PC macOS cannot connect. It didn’t work although I try disconnect and reconnect. What was happened, please help. Thank you.