Getting an error while trying to download a modpack

[H8M8]

Im getting an error when trying to download a pixelmon modpack called pixelmon reborn 5.1.4, the error says it failed to download and to consult the modpack author, ive already downloaded many other pixelmon packs so this is new to me, I've tried deleting the pack and reinstalling it multiple times and logging out of my account and back in to no avail of fixing the problem, does anyone have any suggestions to getting this to work. 

P.S: When trying to download from the launcher it likes to show negative percent then gives me the error, maybe this info is useful

Thanks in advance, Grant