No game sound on Discord

I’m playing Warthunder on Xbox Series X. My headset (SteelSeries) is connected through the 3.5mm jack on the controller to the Xbox. The problem I face is that I can either hear the game sound or the chat. I can’t hear both. I can toggle between the two through the Headset Chat Mixer setting in Xbox Discord. It seems it can only toggle between Discord chat or game sound. What am I missing?

Instructions for the set up or screenshots would be so awesome!