Bitdefender warning about my website's certificate being expired, but it's not.

My website has valid security certificates when I test it using the online certificate checkers. However, on one on my computers, I use BitDefender and when I browse my site, Bitdefender gives me this warning: "firefox.exe attempted to establish a connection relying on an expired certificate to chi11.stablehost.com. We blocked the connection to keep your data safe ..." However, it still allows me to view the site, so whatever it is blocking isn't visible. And this happens no matter what browser I try.

Several months back, I moved my website to a different shared hosting company and my site is no longer hosted on the website mentioned in the warning, chi11.stablehost.com, which was my old hosting company. So not sure where BitDefender is finding that reference to the old server? And when I browse my website using different computers using different antivirus programs (other than Bitdefender), they do not flag the site or block anything. Also, as an added detail, I use Cloudflare with my website, so that is supposed to hide the actual server's name that it is hosted on.

Any suggestions how I can figure out where Bitdefender is finding the connection to my old server and how I can correct that?

And I did report this to Bitdefender as a false positive, but got no response back. Also I cleared my browser cache and flushed my PC's DNS cache. No change though.