Deleted Emails

I noticed that after Hotmail transitioned to Outlook, i had some emails that I had for years, disappear from my inbox. I assumed it was because I was on a mobile device. Checked from my laptop and those emails are now gone. I can’t even find them in the deleted box and I see that my inbox emails continue to be deleted automatically. How can I recover these emails I had for years and how do I stop newer emails from being automatically deleted. I don’t have any rules nor scheduled clean up. Help!