right speaker for calls

Ask your dealer about this.

they can not find the answer

Call up Mitsubishi's technical support.

Either the audio system is defective, the speaker wire is not connected or the speaker is defective. Go back to the dealer and insist they fix it since this vehicle in still under warranty. If they don't, then have a conversation with the Mitsubishi regional rep (number available in your owner's manual).

If the right speaker works when playing the radio the problem is probably software related.

There is a fix for this. HTere are you tube videos on how to enter the hidden Menu for Mit Outlander find that video and enter the hidden menu to select what side the audio comes from