Email to paperwhite not working

Current edition paperwhite. I convert powerpoints to pdf via smallpdf.com and email them to the kindle to study from. I've done this 3-4 times in the past (a few weeks ago) without issue.

Today, I send the email just as I did last time, my email server says its sent, but nothing shows up in my Kindle library. Tried to multiple times and even from multiple wireless connections. Kindle still downloads books from Amazon without issue.

Ideas?