Laravel Cashier Braintree Multiple Subscription for one User

I'm using laravel cashier on a yearly subscription based app and yearly subscriptions are working well. But now i want to allow users to subscribe for more than a year. so they should be able to pay for 3 years or 5 years in advanced and i can't find anything online with regards to this.

Currently, this is how i create subscription

if ($account->newSubscription('main', $plan->braintree_plan)->create($request->payment_method_nonce)) {
          return ['success' => true, 'message' => 'Subscription Successful'];
        }else{
          return response()->json(['error' => 'Error msg'], 401);
        }

via Chebli Mohamed