OBS is set up to stream to only one streaming platform at a time. Full disclosure, there is a way to stream to 2 platforms directly from OBS, but they require a super fast internet connection and a very fast computer to achieve, and you won't be able to record your stream locally from OBS at the same time. If you're interested, HERE'S a YouTube video on the subject.

A better way is to use a service multi-streaming like CASTER.IO, where you can easily and dependably stream your event to multiple platforms at the same time. NOTE: There are other multi-streaming platforms, but at the time this was written, castr.io seemed to offer the best price for a dependable service.