Endless SPAM

Hi!

I have been an "iCloud" user since it was first MobileMe. I've never had any issues keeping my mailboxes junk free.

Yesterday, I went to "swipe" to send the obvious spam message to the junk folder when it clicked open instead. I sent it to junk from there, but every minute or less following, about 26 hours worth now, I have received what appears to be the same email. I've tried moving them to junk, I have set up multiple rules to send them to junk and delete. Nothing is working. I feel like I am losing my mind and I cannot keep track of my legitimate email at all.

The messages say they are coming from postmaster@lithiumtechnologies.onmicrosoft.com

I cannot find anything on this email when I google it, and there as been no other information about this happening to anyone else.

Please help me if you can! This is all driving me absolutely nutty and I can't focus at all because every single minute or less the buzzing/beeping/reminder that this is all happening keeps bringing it fresh in my brain.