Recorded audio with a dji mic only on the left side.

Whenever I try and use audio channel to get the right side to use the left side audio it goes on mute. Tried using the effect "fill right to left" the audio goes on mute again. Tried to modify through the source bin and it still goes on mute. Everyway I try to manipulate the audio to be heard from both sides it goes on mute.

Any suggestions