Error in Live Server.

Upload video in live server firstly convert video in .mts format to .mp4 using FFMpeg Converter but convert video successfully .mp4 but i have face a problem it's video play in local but not upload in live server what is issue.

it' s my code

var wwwrootPath = webHost.ContentRootPath + "\\wwwroot\\UploadVideo\\";
if (CategoryVideo.FileName == null || CategoryVideo.FileName.Length == 0)
return Content("file not selected");
var path = Path.Combine(
wwwrootPath,
CategoryVideo.FileName);
using (var stream = new FileStream(path, FileMode.Create))
await CategoryVideo.CopyToAsync(stream);
string fileExt = Path.GetExtension(CategoryVideo.FileName);
string thisFileName = CategoryVideo.FileName;
if (fileExt != ".mp4")
{
string input = path;
string filenameWoExt = Path.GetFileNameWithoutExtension(CategoryVideo.FileName);
var ffmpeg = new NReco.VideoConverter.FFMpegConverter();
Convertvideo(input, Path.Combine(
wwwrootPath,
filenameWoExt + ".mp4"), NReco.VideoConverter.Format.mp4);
thisFileName = filenameWoExt + ".mp4";
System.IO.File.Delete(path);
}