I am not an Ubuntu power user, but years ago opted for this over Windows and never regretted it.
Recently upgraded from 16.04 to 18 and all was fine until this morning. Logged in first thing, did some work, logged out. Came back later to log in but repeatedly being told password is incorrect. Have restarted multiple times. Can't even log in through the tty.
Please help. I need to get month-end invoices out urgentlyand am now dead in the water.