Waveform is grayed out and no waveform present in multitrack window

I just recorded a podcast and this is the very first time this has happened. There is a gray file on the timeline that goes the length of the podcast, however there is no waveform and no playback. When I export the file there is no playback either; just an hour and 13 minute blank file. Ive tried to relink media with no success. If anybody has a solution please help! I havent found anything online that fixes the problem.