Interacting with people via app/website problems

I've experienced these problems while trying to trade Rocket League items with people:

• The Xbox app is unable to find the person I'm looking for

1. I search for a valid gamertag using the Xbox app > Friends List > "Find People"
2. Unable to find that person
3. I open the Xbox.com website and search for the same gamertag
4. Their profile magically shows up

• On desktop I'm unable to message a person that is not on my friends list
  1. Continuing from above, I click "Message" on the person's profile
  2. It takes me to my own message list (why? just let me message that person)
  3. I click "New Message" and it will only allow me to choose someone from my friends list

So.. in order to complete a Rocket League trade with a complete stranger, I have to hope they show up in the Xbox app, otherwise I have to add them as a friend on the desktop website or use the Xbox itself to manually search in order to contact them. Surely
this isn't by design.

:)