Recording error after conversion

[helpplease123]

I recorded a meeting that was an hour and a half long.  After the meeting, my computer froze during the conversion of the recording.  When I open the meeting file, it only has 30 minutes of audio available, however it shows that there was a full hour and a half (the end of the meeting is in silence), and no video is available for the entire meeting.  The video file is in MP4 format and I am not clear of how to fix this issue.  Please help!!

[MPac52]

Similar issue except we have a several recordings where everything is great but then the audio suddenly is garbled and broken, even though during the meeting there were no audio issues whatsoever. Local Recording was used. I think the files may be corrupted.