@NeilR_M I've tried checking and changing the IPsec settings, but it doesn't seem to work. These are the settings on the router.

I have 2 TP-Link ER605 and ER706W-4G routers with subnets 192.168.0.0/24 and 192.168.10.0/24 configured with an IPsec VPN. Each router is behind an ISP modem, and since the WAN IP of the ER605 is not...