Repair Corrupted GoPro 60 FPS Videos

Two 60 FPS GoPro clips refuse to play past the 20- to 30-second mark in Windows Media Player. One file runs 2 min 38 sec, the other 5 min 38 sec; both freeze while the audio continues to the end. I need them fully restored so they play from start to finish at their original frame rate and resolution.

I will share the raw MP4s via cloud as soon as the project starts. Feel free to use whatever toolset you trust—FFmpeg, GoPro SOS utilities, Grau Video Repair, or your own custom workflow—as long as the repaired versions:

• open in common players (Windows Media Player, VLC) without freezing or desync
• retain the original 60 FPS and visual quality (minor re-encoding is fine if imperceptible)
• are delivered back to me within 5 days

Please confirm your experience with corrupted GoPro or H.264/HEVC MP4 repair when you respond, and let me know any additional information you might need to get started right away.