Wrong files

[FeRoPi]

I was downloading the dvd image for the amd64 port of debian. When I
got the 91% of 4.4GB it stops. I tried to resume it but it didn't work
so I started to download the file again and only downloads 379MB!!! I
tried to download the i386 fdvd iso but it does the same. What can I
do? Thanks.