Legitimate Mail Going to Junk

Hi, I have an issue whereby mail from every person at a particular company is going into junk on my iMac running Big Sur. I have added every email address impacted to my contacts but it still happens.

There used to be a way where you could mark as "Not junk" but that option seems to have disappeared.

I saw that there was a thread on this issue around August last year but no solution ever seemed to arise even though it seemed that a high number of users were impacted.

Is anyone else having this issue?

With the powers of AI right now, you would think that Apple could create a smarter junk filter than exists at present. How can it be so bad, I just don't get it?