Unable to connect to https://launchpad

Hi,

I'm having issues connecting to launchpad from our network.

Tried to do a "add-apt-repository ppa:certbot/certbot", it will stalled and when the request is cancelled, it will show that the network is not reachable.

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 326, in get_ppa_info
    ret = get_ppa_info_from_lp(user, ppa)
  File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 101, in get_ppa_info_from_lp
    return get_info_from_lp(lp_url)
  File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 95, in get_info_from_lp
    return get_info_from_https(lp_url, True)
  File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 88, in get_info_from_https
    data = _get_https_content_py3(url, accept_json)
  File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 126, in _get_https_content_py3
    raise PPAException("Error reading %s: %s" % (lp_url, reason), e)
softwareproperties.ppa.PPAException: 'Error reading https://launchpad.net/api/1.0/~certbot/+archive/ubuntu/certbot: [Errno 101] Network is unreachable'

Have tried to do a traceroute to launchpad.net and it will time out as well. Is there anything that may be blocking the connection?

ryan@test:~# traceroute launchpad.net
traceroute to launchpad.net (91.189.89.223), 30 hops max, 60 byte packets
 1 162.148.119.103.static.lws.sg (103.119.148.162) 0.189 ms 0.186 ms 0.175 ms
 2 203-174-85-121.rev.ne.com.sg (203.174.85.121) 0.243 ms 0.269 ms 0.242 ms
 3 10.15.62.222 (10.15.62.222) 33.475 ms 33.431 ms 33.305 ms
 4 * * *
 5 * * *
 6 SOURCE-MANA.ear2.London1.Level3.net (212.113.8.154) 250.470 ms 250.479 ms 250.434 ms
 7 * * *
 8 * * *
 9 * * *
10 * * *
11 * * *
12 * * *
13 * * *
14 * * *
15 * * *
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18 * * *
19 * * *
20 * * *
21 * * *
22 * * *
23 * * *
24 * * *
25 * * *
26 * * *
27 * * *
28 * * *
29 * * *
30 * * *

Thank you.