Same here.  Apple Mail.  There seem to be a lot of users with the same problem.  Hello Seeking Alpha!

I also started getting these problems. I think it may be related to the latest Apple security patch I applied to my Mac. I also added the Seeking Alpha e-mail addresses to my iCloud contacts to see if that resolves the issue. It's really frustrating that I have not heard from anyone at Seeking Alpha.

Well, I changed my email address and now get all the email.  Any know whether the Apple security additions can be controlled?

Same here. Also Apple Mail. Very frustrating!