Injected ads disguised as emails at the top of my inbox right before I click on a new email.

Hi, when I go to click on a new email, just before I click, an ad disguised as an email pops up and shifts my emails down. This is super strange! This causes my cursor to miss the email I wanted to click on and makes me click on an ad that I didn't want to click on. Can someone from Microsoft please help. Is this intended behavior for Outlook online? Thank you!