iATKOS | United Kingdom

I’m having issues with logging in after upgrading my 2012 27” iMac to Tahoe. I didn’t get a chance to update the patch because once my iMac restarted and I tried logging in it said my password was incorrect even though I never changed the password and have had the same one for years, so I know what it is. I was able to get into Terminal and change the password and once again it says that it is incorrect when I know I’ve entered the password correctly. I tried a few other start up options which didn’t work, but now I only have the option to select MacOS start up, which brings me back to sign-in. Am I missing something? I have had a few minor issues similar to this before, but I was always able to fix it