Outlook Deleting Certain Email Before Delivering to my Mailbox (Not Even Going to Junk)

Thanks. It’s blocking far more emails than previously. Including from reputable companies (for example Emirates Airlines and American Express emails). Some senders who have previously successfully delivered are unable to deliver. Some get non-deliverable reports others don’t. But I’ll try to ask thanks that’s a good idea. It seems like there’s a 50/50 chance of non-personal emails being blocked. Do you know if there’s any way to fix this or someone I can contact for help?