I cannot access to GitHub only on my Ubuntu 18.04 machine and all other machines (Windows PC, iPad, Phone) connected to the same network can access GitHub.

When I try to ping GitHub, I get

The result of run nslookup github.com:

Server:     127.0.0.53

Address:    127.0.0.53#53



Non-authoritative answer:

Name:   github.com

Address: 192.30.253.112

If I try sudo route -n:

Kernel IP routing table

Destination     Gateway         Genmask         Flags Metric Ref    Use Iface

0.0.0.0         192.168.178.1   0.0.0.0         UG    600    0        0 wlp4s0

169.254.0.0     0.0.0.0         255.255.0.0     U     1000   0        0 wlp4s0

192.168.178.0   0.0.0.0         255.255.255.0   U     600    0        0 wlp4s0

If I ping google.com, it works.

I can't access GitHub in the browser also. However, all other websites work fine. Also, I can access GitHub on other devices. Is there anything wrong with the DNS?