I have website monitors set up on a server. They have been working for months. Within the last week, the websites have been showing up as unavailable on my dashboard (red dot).

Alerts come and say they can't be reached then later say they can. We check the sites and they're up all during these periods. I go to the monitor page and test the sites (as below). Sometimes the test connects and sometimes it doesn't. Even when it does connect, the red dot shows next to the website name (below) and the dashboard still shows as down.

I originally thought it could be that the SW server loses connection to the application server but the node consistently shows as up. I've tried restarting the sites and restarting the SolarWinds service on the server. Currently the dashboard shows the sites down for 5 days though they've been up every time we checked and the SW tests (above) have shown they were up at times.
I guess I have three questions...
1. Why would SW say the sites are down when they aren't.
2. Why would the dashboard still show them as down when the test successfully connects.
3. Can someone offer me suggestions to fix this.
Thanks