Our company VPN keeps being blocked by xFi Advanced Security

We have 120 employees.  Those with xFi Advanced Security enabled get blocked from accessing our WireGuard based VPN.  (WireGuard is definitely a mainstream VPN system, not something weird.)  They can use it for a little while, and then it gets blocked after some time... and doesn't ever come unblocked.  We have to instruct them on how to whitelist the connection for 30 days in the xFi gateway, and then we have to instruct them again when it reliably gets blocked when that whitelisting expires.  This is not sustainable and definitely not okay.  Right now we have an employee staying in a house where they don't control (nor have access to) the xFi gateway, and so they can't whitelist the VPN.  Now they have to use their Verizon phone's hotspot, and that's a very bad situation since they're on a metered plan.  What can we do?