Added rules without without users authorization

I have a website and it sends a lot of email to the users to confirm their form submittion

I have being receiving a lot of weird forwarding messages when sending confirmation to Hotmail/Outlook emails and it is reducing my mail server IP reputation

There is a lot of cases on this forum of people complaing about it and it seems like hackers are using some Outlook/Hotmail/Live/MSN vunerability and MS is doing nothing about it

https://answers.microsoft.com/en-us/outlook_com/forum/all/my-outlook-rules-has-been-hacked/19cde21f-6cd7-4157-af9f-8b0ac1e5ab8e

https://answers.microsoft.com/en-us/outlook_com/forum/all/i-was-hacked-and-i-think-they-are-forwarding-my/93dd7c14-0900-48ab-bc5a-a9be306289b8

Can anyone help?