In general, the issue may not be related to the hosting service itself when it comes to email messages not reaching the Inbox.
When sending messages to other services such as Gmail, Yahoo, or any other official email service, they may reach the Inbox, while your messages may end up in the SPAM folder in Hotmail. Or, your messages may reach the Inbox in Hotmail but be received as SPAM in another email service, or they may not reach everyone's Inbox.
From here, we can understand that the website has not been activated by the email provider as a legitimate email sender. Therefore, any website that sends emails to Hotmail may have its messages classified as (SPAM).
So, you should simply contact Hotmail and inform them about this issue. The matter will be reviewed, and an agreement may be established between you and them. It may take some time, possibly up to a week, until the issue is resolved. After that, everything should be fine.
