Thank you forum. The problem of "Unable to login to EPFO Portal" still exists as of today. I tried multiple times, it kept showing invalid UAN/Password and there is no chance I forgot my password as I usually save it. So it is a bug in their technical website. I also could not reset password as the Aadhaar OTP page kept giving me error. So I finally found answers in this forum and used the UMANG App.
Now the next question is how will I do online transfer of PF as I have recently changed my company ?