Since hotmail changed to outlook, emails were lost and continue to be deleted

I have read several posts on how this has affected others and and am incredibly frustrated myself. I lost most of my emails which were not able to be recovered when the change happened and I continue to open my inbox with emails deleted. This is ridiculous and though I have searched and followed whatever steps I have found, I can not seem to fix this. I did see a thread where it was suggested to look into "sweep" which I am not familiar with and can not find in my account- could there have been an automatic setting that microsoft/outlook put on it (which they shouldn't have) that I can shut off? This needs to be fixed.