Using classic Outlook for Windows in business environments
A quick update: I went back and removed all the contacts that I had (I have a backup) and then I set the "Reading Pane" to OFF. I then added 3 contacts and I went back and forth between mail, calendar, and contacts and it seems to have been fixed, for now, the issue
I realized that this is not optimal for someone like me, who may have lots of contacts. This is because each contact needs to be removed individually one by one. This is tedious and counterproductive to what Microsoft preaches: High productivity. But it is working for me for now. I will keep digging and I will keep you guys posted