Either do it by certified mail or in person
They do not have one close to Spirit Lake Idaho.
If you still have the contact it will tell you what to do and gie you the numbers you need to cancel. Be aware they charge a fee to cancel early.
You have to put it in a 30 day cancellation notice in writting. Id keep a copy for your records, also i think you need to send it to the location you originally signed up at.
You will have to contact them directly, this is Google. Planet Fitness is all over the US
Thanks! Your answer is awaiting moderation.