How can I pass JavaScript variables to Laravel route?

This is my route

Route::get('user/checkout/id={id}&subscription_id={subscription_id}&access_token={access_token}', [CheckoutController::class, 'checkout_after'])->name('user.checkout_after');

This is my js, but the problem is I get undifined variable error for the subscription_id. Other 2 parameters ok.

onApprove: function(data, actions) {


        <?php echo $subscription_id ?> = data.subscriptionID;
        

        window.location.href = "{{ route('user.checkout_after', ['id' => $plan->id, 'subscription_id' => $subscription_id, 'access_token' => $access_token]) }}";

       }