Welcome to the RingCentral Community

Thanks Phong for your valuable solution. Now the Ringout is working from the sandbox account.

Hi,

I am not sure if you really want to use the ring out feature. But as you described, I think click to dial is the goal you want to achieve. So do check out these possibilities and let me know if you have questions:

1. https://github.com/ringcentral-tutorials/ringcentral-widgets-demo
2. https://github.com/ringcentral-tutorials/ringcentral-embeddable-demos

Or check if using the WebRTC could be what you need.
2. https://github.com/ringcentral-tutorials/getting-started-with-webrtc-js-demo

If you want to use just ring out feature, please read this tutorial https://ringcentral-api-docs.readthedocs.io/en/latest/calls_ringout/

Hope this helps!

+ Phong