Stripe issue when creating subscription: "Could not determine which URL to request"

I've setup stripe multiple times and never had this issue before. I'm processing the "customer created" web hook and using the payload to attach stripe id to my user and setup a new subscription.

I'm getting the following error:

Stripe\Exception\UnexpectedValueException: Could not determine which URL to request: Stripe\Subscription instance has invalid ID:  in file /Users/mick/repos/askit/vendor/stripe/stripe-php/lib/ApiResource.php on line 107

This only happens when I try to create the new subscription. Here is my full controller:

public function handleCustomerCreated(Request $request)
    {
        $payload = json_decode($request->getContent(), true);

        $user_id = $payload->data->object->subscriptions->data[0]->metadata->user_id;
        $subscription_id = $payload->data->object->subscriptions->data[0]->id;
        $stripe_customer_id = $payload->data->object->id;
        $current_period_start = $payload->data->object->subscriptions->data[0]->current_period_start;
        $current_period_end = $payload->data->object->subscriptions->data[0]->current_period_end;
        $stripe_plan = $payload->data->object->subscriptions->data[0]->items->data[0]->plan->id;
        $name = $payload->data->object->subscriptions->data[0]->items->data[0]->plan->nickname;
        $stripe_status = $payload->data->object->subscriptions->data[0]->status;
        $interval = $payload->data->object->subscriptions->data[0]->items->data[0]->plan->interval_count;

        $user = User::query()->find($user_id);
        $user->stripe_id = $stripe_customer_id;
        $user->save();

        $subscription = new Subscription();
        $subscription->user_id = $user_id;
        $subscription->name = $name;
        $subscription->stripe_id = $stripe_customer_id;
        $subscription->stripe_status = $stripe_status;
        $subscription->stripe_plan = $stripe_plan;
        $subscription->interval = $interval;
        $subscription->current_period_start = $current_period_start;
        $subscription->current_period_end = $current_period_end;
        $subscription->subscription_id = $subscription_id;
        $subscription->save();

    }

If I remove the new Subscription stuff it works fine, the stripe is getting attached to my user model just fine. The error only happens on this part:

    $subscription = new Subscription();
        $subscription->user_id = $user_id;
        $subscription->name = $name;
        $subscription->stripe_id = $stripe_customer_id;
        $subscription->stripe_status = $stripe_status;
        $subscription->stripe_plan = $stripe_plan;
        $subscription->interval = $interval;
        $subscription->current_period_start = $current_period_start;
        $subscription->current_period_end = $current_period_end;
        $subscription->subscription_id = $subscription_id;
        $subscription->save();

Any ideas? The table was created automagically by Laravel Cashier.