This also started for me recently. @thandungen spooning do you use Microsoft / Office 365 as your email provider?
I noticed I was no longer receiving emails from my contact forms. I then tested this by setting my recipients as my work account (which uses Microsoft for mail), my personal gmail, and my personal yahoo.
Every time I tried, I would receive at gmail and yahoo addresses but not my work’s Microsoft account.
I am thinking there is something that has changed possibly on Microsoft’s side that is causing this.