I keep getting notifications from the person I blocked

I have been having this same issue for years, but it only seems to be with 3 particular gamertags. I have contacted Microsoft multiple times, but even they couldn't fix it. Did you ever find a solution?

Hey Flufy_Shadow,

I’m sorry to hear about any issues you may be having. If you haven’t already, please go ahead and make a new thread detailing your issue and any troubleshooting steps (if any) you’ve tried
so far. That way we can tailor our support specifically to you!

Thank you!

Tried removing my profile from the Xbox and re-adding it. Nope. Still getting the same "[Insert blocked person's gamertag] is broadcasting [Insert game] on Mixer" and "[Insert blocked person's gamertag] is online" notifications. Also tried unblocking him
and re-blocking him on the Xbox App on Android and then Windows 10. Nope. Still getting unnecessary notifications from him, even if I go into "Do not disturb" mode. Just no matter how many times I block him, I still get unnecessary notifications from him!
This is really frustrating me!

At this point, the only solution I can even think of is to unblock the person in question and put him back in my friends list. He hasn't even blocked me yet, despite having told me in a message that he would block me only to not actually do so.

I have blocked them and reported them seems I always end up getting a message notification from the player

you don't reply to the person

If you do you will unblock them

Retailiation isn't allowed

Just keep blocking and reporting the accounts. I know it's a pain, but that's all you can really do. Might be worth changing your notification settings so that you're not spammed so much by message notifications from this individual...