Error showing when I entered command "apt update"

Question

Hit:1 http://security.ubuntu.com/ubuntu focal-security InRelease
Hit:2 https://dl.google.com/linux/chrome/deb stable InRelease                  
Err:3 http://in.archive.ubuntu.com/ubuntu focal InRelease                      
  Cannot initiate the connection to in.archive.ubuntu.com:80 (2403:8940:3:1::f). - connect (101: Network is unreachable) Could not connect to in.archive.ubuntu.com:80 (43.255.166.254), connection timed out
Err:4 http://in.archive.ubuntu.com/ubuntu focal-updates InRelease
  Cannot initiate the connection to in.archive.ubuntu.com:80 (2403:8940:3:1::f). - connect (101: Network is unreachable)
Err:5 http://in.archive.ubuntu.com/ubuntu focal-backports InRelease
  Cannot initiate the connection to in.archive.ubuntu.com:80 (2403:8940:3:1::f). - connect (101: Network is unreachable)
Reading package lists... Done                              
Building dependency tree       
Reading state information... Done
All packages are up to date.
W: Failed to fetch http://in.archive.ubuntu.com/ubuntu/dists/focal/InRelease  Cannot initiate the connection to in.archive.ubuntu.com:80 (2403:8940:3:1::f). - connect (101: Network is unreachable) Could not connect to in.archive.ubuntu.com:80 (43.255.166.254), connection timed out
W: Failed to fetch http://in.archive.ubuntu.com/ubuntu/dists/focal-updates/InRelease  Cannot initiate the connection to in.archive.ubuntu.com:80 (2403:8940:3:1::f). - connect (101: Network is unreachable)
W: Failed to fetch http://in.archive.ubuntu.com/ubuntu/dists/focal-backports/InRelease  Cannot initiate the connection to in.archive.ubuntu.com:80 (2403:8940:3:1::f). - connect (101: Network is unreachable)
W: Some index files failed to download. They have been ignored, or old ones used instead.