Zerotier over LTE - possibly simple?

Hi everyone,
I am new to openWRT so this might be easy to solve. I have flashed an older LTE modem/router (Tp-link Archer MR200) with openWRT and installed the zerotier package.
While connected to internet via WiFi (client mode + NAT) i had no problem connecting to Zerotier network from the router itself or the connected devices.
( i followed
However when I am connected to the internet over the integrated LTE modem, the zerotier service on the router fails to connect, even though other devices connected to the internet via the router are able to connect reliably to zerotier network over the cellular network.

There must be something I am missing in the config of the router itself, maybe how it routes traffic from the cpu?


EDIT: per @mk24's comment below, my question may not be relevant. striking through...

Is this an inbound or outbound connection that is not working properly? If inbound, have you verified that you have a public IP address on the WAN? It is common for mobile operators to provide CG-NAT or even RFC1918 NAT addresses, so you may not have a publicly routable IP.

I've used Zerotier over LTE. It will work even through CG-NAT at both ends, since it connects through Zerotier servers that have public IP addresses.

It is possible that your LTE company is blocking it. Also if you're running IPv4 only, make sure IPv6 is fully disabled.


@mk24 Thanks for the reply!
LTE provider is unlikely to be blocking it as other devices connected to the internet over the LTE through the modem are able to connect to zerotier no problem.

It seems like zerotier is unable to reach the servers, it is always stuck on "REQUESTING_CONFIGURATION"

I have disabled every IPv6 setting i could find - in devices, and interfaces
Still the same thing :

root@OpenWrt:~# zerotier-cli listnetworks
200 listnetworks <nwid> <name> <mac> <status> <type> <dev> <ZT assigned ips>
200 listnetworks 8056c2e21c000001  02:81:23:75:f3:2e REQUESTING_CONFIGURATION PRIVATE ztmjfmfyq5 -

The router itself has no trouble accessing the internet either, when connected via ssh i can ping , wget any website, just for some reason zerotier fails to connect.

thanks for replying! anyway.