Invalid Checksum.

I am getting Invalid checksum error when I try to get access token using request token.

kite.request_access_token(request_token , my_secret_key)

This part of code ends up giving an error saying

File "/usr/local/lib/python2.7/dist-packages/kiteconnect-3.1.4-py2.7.egg/kiteconnect/__init__.py", line 214, in request_access_token
File "/usr/local/lib/python2.7/dist-packages/kiteconnect-3.1.4-py2.7.egg/kiteconnect/__init__.py", line 443, in _post
File "/usr/local/lib/python2.7/dist-packages/kiteconnect-3.1.4-py2.7.egg/kiteconnect/__init__.py", line 525, in _request
kiteconnect.exceptions.TokenException: Invalid checksum

My code was working fine last week. It is giving these errors when I tried to run this today. Can anybody please tell me what's wrong? Thanks.