Second monitor not recognized

Please see EDIT

On an older Dell laptop i clean reinstalled windows 10 build 19041.572 on a new larger ssd. it is attached to a tv with hdmi as a second monitor which was working as expected after the update. I got it all set up but could not get it to allow me to start up without logging in. No check mark was present to disable that when i ran netplwiz. i ran the reg edits found in the tutorials to disable lock screen and to disable require password on wake up. then i restarted. it goes directly to the desktop now without login or welcome screen. but the second monitor is not recognized by windows. the computer makes a chime when the second monitor is plugged in, suggesting the computer recognizes its presence, but does not appear in device manager nor on the display page of windows settings.

EDIT: it was only the tv that was displaying and the intrinsic laptop screen was not, but it turns out ONLY when the laptop lid was closed. when it was opened both screens were identified and their properties could be altered under settings->display. I have the settings for sleep, hybernation, and "when lid closed" set to Do Nothing in advanced power settings. I don't quite understand this, and it wasn't this way before as far as i know, though i can't say for sure since i never really looked at the display settings page after setting it to display on the tv. Anyway as long as i know how to deal with it i'm ok with the way things are. I've just added this explanation in case anyone else runs into the same issue.
If anyone can explain why this happens i'd be interested in knowing.
thanks for your time. sorry to have incompletely explored the situation before i posted and maybe wasting your time.