How to avoid emails being marked as spam from Microsoft trusted senders?

Step 1: Sign into your Office admin account via https://portal.office.com

Step 2: Navigate to Exchange admin center.

Step 3: On the left pane, scroll down and click More features.

Step 4: Click open under Permissions.

Step 5: Click Protection on the left pane.

Step 6: Switch to the connection filter tab.

Step 7: Double-click on the default policy or click on the edit icon.

Step 8: Check the Enable safe list checkbox and click Save.