To live-webcast in YouTube, check the following points.
- Live webcast is enabled for the channel.
* In YouTube help, refer to "Enabling live Streaming":
https://support.google.com/youtube/answer/9227509?hl=en
- Are 1,000 or more people subscribed to the channel?
* To live stream on mobile, your channel will need to have at least 1,000 subscribers in addition to the requirement above. In YouTube help, refer to "Limitations on live webcast."