GL-E750 cannot ping or Traceroute with VPN active also routing is not working

I tried to install Tailscale on Mudi Router by following different resources online. Such as:

So far I was able to connect the router to tailscale and I can from any tailscale device reach (ping, ssh, web access) the router. But, the other way round is not working.

First, I noticed that when I run Tailscale the ping command is not working (I believe DNS is not correctly resolving). The picture attached is exactly the error I am getting, and the same for traceroute and nslookup.

From any device connected to the router I can use ping to google.com for example but I cannot ping to any Tailscale device (somehow the routing table is not considered at all!)

Device Information:
Name: GL.iNet GL-E750
Firmware: 4.3.19 (0319release3)
OpenWrt Version: OpenWrt 22.03.4 r20123-38ccc47687
Kernel Version: 5.10.176

how about the IP ping?
ping 8.8.8.8
ip r
ifconfig

did you set-up a exit node in the E750? if yes, what device as the exit node?
and did the exit node work ok? like test it via the Tailscale APP in phone.