Dear Sir/Ma'am,
1. Check if the internet connection is working properly.
2. Ensure that the antivirus and Windows firewall are turned off, and uncheck the IPv6 option.
3. Ensure the correct Login ID and Password are entered.
4. Log out the learner by pressing Ctrl + Shift + R.
If issue still persist generate the SOLAR ticket with Below details.
Learner Code
Course Name
Screenshot of issue