suddenly can't stream to twitch

Hello I have been living here for a few months and streaming 4+ days a week and recently i have been unable to connect to twitch thru OBS. Constant disconnects. If I use a VPN this issues is gone for the most part. I'm paying alot of money for this service. Why am I being throttled and how do i solve it? I am connected to the modem with an ethernet cable and my PC is top of the line. Thank you.