This is a common issue when new updates come out. Most servers running paper or spigot don't update right away due to needing spigot+paper to update and also making sure their most important plugins won't stop working.
I would reccomend either waiting a couple of days before updating until your severs catch up, or using multiple minecraft installations (called instances) for different versions of the game you play on. I use PolyMC launcher to manage my instances, but I believe the official launcher has this feature built in now as well.
