HTTP_RANGE is not working on video seek bar

Question

I am trying to stream a mp4 file using ASP/VBscript. I use ADODB.Stream to lunch the file and some codes to detect that which range is requested by user. The video is being loaded successfully but by clicking on seek bar nothing happens. I have set all Accept-Ranges , Content-Range and Content-Length in response headers:

HTML code:

<video controls>
<source src="video.asp">
</video>

video.asp

filename ="test.mp4"

Set objStream = Server.CreateObject("ADODB.Stream")
objStream.Type = 1
objStream.Open
objStream.LoadFromFile(server.mappath(filename))
sizebyte=objStream.size

Response.ContentType = "video/mp4"
Response.AddHeader "Accept-Ranges", "0-" & sizebyte

'Checking if user requested a range (by clicking on seekbar)

if Request.ServerVariables("HTTP_RANGE")<>"" then
    'Cleaning startbyte from (bytes=) and (-)
    startbyte=replace(Request.ServerVariables("HTTP_RANGE"),"-","")
    startbyte=replace(startbyte,"bytes=","")

    Response.AddHeader "Content-Range", "bytes " & startbyte & "-" & sizebyte-1 & "/" & sizebyte
    response.AddHeader "Content-Length", (int(sizebyte) - int(startbyte))
else
    response.AddHeader "Content-Length", sizebyte
end if

do while not objStream.EOS
    response.binarywrite objStream.Read(1024000)
    Response.Flush
loop

objStream.Close
Set objStream = Nothing
Response.StatusCode = 206