We've implemented a new Premium feature, called "Set Captcha".
Typing "Set Captcha" in a group with your Premium will provide you with simple instructions of how to use the feature.
You can check the Premium Commands section here for a step-by-step guide, as the feature is a bit complicated.
Please contact us in Ragebot Premium Support if you experience any issues.
P.S., some new free features are coming soon, stay tuned!