If you keep more than one browser on you PC, you can try using a browser that does not have the login info saved (use Chrome or Firefox, rather than IE/Edge). You can also try opening your browser in incognito or private mode, as that may stop the auto-fill. You may also be able to access the list of websites for which passwords are saved, in your browser settings, and manually delete the info for your MS account. Auto-fill can be handy at times, but a pain in the rump for others. Hope you find a solution.