Hello
Can you do this on a computer, go to www.outlook.com, click on the gear icon on upper right to launch settings, then in the Mail tab , go to junk, scroll down and see if that's the block list you checked?
Otherwise, any chance you blocked yourself on a smartphone? On your phone's contact app, look for blocked list too. For example, if it is iphone, you can launch settings app, then search for blocked contacts, and review there, see if it might be blocked on device level instead.