Doesnt matter, 1 hour or 30 days, you paid for a month, started using it, then YOU broke the ToS and got banned - chargeback after that is fraud.
Actually even if you paid and never logged in once, and never used a bot, then did a chargeback thats still fraud - whether you used it or for what length of time doesnt matter, your account was active on Trion's servers so you got charged for it, simple as that, cant get a refund part-way thru a month, once you paid you paid.
P.S. I have a WoW subscription that expires in September that I havent touched in 4-5 months, but I cant get my money back, I paid for it and its live on Blizzard's server, whether I use it or not is up to me.