qBittorrent Windows CURL POST data results in 400 bad request

[C0nw0nk]

curl -s -b "\cookie.txt" -c "\cookie.txt" -X POST -d "hashes=%torrent_hash%?value=true" --header "Content-Type: application/x-www-form-urlencoded" --header "Referer: %webUI%" "%webUI%/api/v2/torrents/setForceStart"

I am trying to force start a torrent hash but keep getting a 400 bad request i think it is to do with my CURL command line. If i am not trying to do a POST request it works fine but this particular function to make qBittorrent force start a torrent download seems to require it to be a POST request.

https://github.com/qbittorrent/qBittorrent/wiki/WebUI-API-(qBittorrent-4.1)#set-force-start

Anyone know the correct way to do this thank you ?