Hi @Lucentia Gems ,
This could be normal for new domains.
Please setting up a Junk Email Reporting Program (JMRP) account with the new IPs by clicking the link below. Hopefully this can help whitelist your domain.
https://sendersupport.olc.protection.outlook.com/snds/JMRP.aspx
Moreover, below are some official document about this problem for reference:
By the way, actually the Outlook-* tags are dedicated to supporting issues related to the Outlook desktop clients, questions about outlook.com or hotmail is currently not supported in Q&A and are supposed to be posted in the community below:
https://answers.microsoft.com/en-us/outlook_com/forum/outlk_com
In case the above information doesn't work, and you need further help on this, it's suggested to repost to the aforementioned outlook.com forum instead.
Here's also one similar thread I found there and you can take a look at it: All emails from my domain are being sent to junk by hotmail.
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