Xr500 zerotier

i have 2 devices with the same configurations and working without any problem, but after a couple of hours i lose connection on the xr500 and cant acess the other router over the zerotier connection, but if i rebbot the xr500 all the connection start to work normaly, what could be the issue

Model Newifi-D2
Architecture MediaTek MT7621 ver:1 eco:3

Model Netgear Nighthawk XR500
Architecture ARMv7 Processor rev 0 (v7l)

i followed this configuration step by step and works, but after 4-5 h the xr500 stops seeing the newifi-d2, when i go to the routers a can see the devices in the network from both sides but from the devices i only can see the locals.