Hey MusicMan!
Sorry for the issues you're having with the PT connection. Let's first start by checking the version of OOTP 23 that you have installed in case that is the issue. If you were part of the Beta testing done via steam we will want to make sure you get out of that beta program. You won't get game updates for official launches and will only get beta builds which could be major issues for connections.
To see what version you have all you need to do is launch OOTP 23 and at the bottom of the main menu will be a version # listed. If you can let me know what version is listed there we can view that. Also we will want to turn on tracemode and have you attempt to sign in again so we can have the program trace what is happening and then send us the file of that trace. That will let me send that on to our dev team to review and make sure there isn't something on the game's end that's causing that communication issue with your internet. Most likely it's a security issue with your internet and the game which could be a couple of different things causing that. You can use this link to get info about how to do the trace file and send that to us. You can send that to me in a DM if you'd like.
https://support.ootpdevelopments.com...debug-log-file
Thanks
Alex