Twitch prime is free, and is included with an amazon prime membership.
There is even no reliable information about his age, but it is known that he graduated from high school this year.
However, you should remember that Streamlabs has been out two years longer than StreamElements.
This means to the streamer the Twitch Prime sub actually provides them more value as a sub when it comes to revenue.
To resubscribe with twitch prime, use your Twitch Prime membership once your subscription expires or pay for the resub.