There is no way to farm enough bits to make it a realistic service.
Based on research, there are limitations to how many ads a Twitch account can watch before no more ads will display or before it's banned for farming.
It appears one account can farm about 500 bits/day, but that's not enough to fill a $5 order. You would realistically need 20+ accounts farming 24/7 to fill orders, but more likely 50 accounts as many would be banned along the way.
Is this what your doing? Can you prove it? If so, please take a screen video of your farming accounts and some of these accounts actively farmings and how many bits they currently have. Upload to Youtube (unlisted) and send me the URL privately.
From my experience, bit service providers say they farm, but are actually charging back payments. You'll have to show a dozen Twitch accounts farming and with 1000+ bits on each account so I can see you're telling the truth. The accounts should also be new, no older accounts as I'll assume they're hacked accounts and you're stealing bits.