After Effect auto fast Forward

I would recommend using the Adobe Media Encoder instead of Hand Brake and render a GoPro Cineform copy of the footage. MP4's are lossy, intra frame compressed, and your quality will suffer. No professional or studio would ever consider using MP4 as a digital intermediate. At best, that would be considered a proxy file not suitable for final rendering.

There is a possibility that your clip is in Variable Frame Rate (VFR). In the project panel, right click / Interpret Footage / Main ... in the section that says Conform to frame rate, set a lower than it already is, it could be 30 frames per second.

If that doesn't work for you, you could try using HandBrake and before importing it into Premiere Pro you transcode it to MP4.