Email notifications from this site are all getting flagged as spam for me.

Also, I'm a tech guru very familiar with forums like this one, used vBulletin for many years (v3 and v4). I highly recommend moving away from the obsolete vBulletin and going to the newer platform created by the original vBulletin developer which is XenForo. I upgraded my 5 forum sites that I run to XenForo such as you can explore at one of my sites and which is a far more modern experience and better for your current and future customers to use.

I'm NOT affiliated with them, just a techie that knows these products well. If you need help let me know.