Welcome to Seven Forums DharamSingh89. Which browser are you using to try and sign in? Have you tried with another browser? I would try to access the sign in page in Safe Mode with Networking and see if it works there. If so, try a clean start to see if you can find a conflict. Safe Mode Troubleshoot Application Conflicts by Performing a Clean Startup
If no help, it will be a tough one since it is specific to that one sign in page, and they have a known issue who's solution did not help you. If you don't have a second browser to test, it is a good idea to download Firefox, or Chrome to have as a second choice if needed, and to test this issue.