A possible reason is that your safe senders are also listed on your Blocked Senders list hence the SmartScreen filter does not recognize it.
I suggest that you check your blocked senders list by referring to the steps below:
1. Go to your mailbox and click Options on the upper right corner of the screen.
2. Click More Options.
3. Under Preventing Junk Email, click Safe and blocked senders 4. Click on Blocked Sender, then locate for the safe sender.
5. Click << Remove from list.
If problem persists, I suggest that you try to open the email using a different web browser.
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