Remove Echo From MP4 Audio

I have a single MP4 that runs somewhere between five and thirty minutes and the microphone captured a strong room echo all the way through. I need that echo removed (or at least reduced to an inaudible level) so the dialogue sounds clean, natural, and “studio”-quality from start to finish... (Budget: $30 - $250 USD, Jobs: Adobe Audition, Audio Editing, Audio Engineering, Audio Processing, Audio Production, Audio Services, Sound Design, Video Editing)