Screensharing login window won't quit

I have had this problem over a year now. We have 3 Macs in the house - two iMacs and my MacBook Pro. Both the iMacs have screensharing enabled in their System Preferences. On my MBP, in the Finder window sidebar I select one of the other mac to view. I get the usual screensharing login window, I enter the info. and hit connect and it never connects. The window will never quit neither can I dismiss the window even by quitting screen sharing app. I have not been able to find the exact process that is responsible for this window in the Activity Monitor so I could atleast terminate the process there. The only way I could then get out of the mess is to log out and then log in. Here's a little caveat. If when the login window is sitting there stubbornly trying to log in and I have quit the Screensharing app, I go back to the Finder window, select the same Mac and hit Share Screen button, it will immediately connect. But the log in window will still sit there and there is no way I can dismiss it other than to log out and log in. - It's really annoying 😀 I have not been able to figure out as to why this happens. Anyone know about this? It's been about 15 minutes now, and the window is still there. It doesn't time out either! Well, I got to go log out now (after I post this post) 😝