Sorry to hear about the trouble. I tested it on my end and seems to be working so could you please launch the Adobe CC Desktop app and check if you are able to sign in from there? Once you are signed in you can launch XD from there.
Thanks for the response. I tried exiting and launching the Adobe CC desktop app again, even restarted my PC. It still didnt resolve, happens randomly. Sometimes the Google Sign-in button shows up & sometimes doesnt.