The token has already been used. Each token can only be used once to create a source. code example

Example: The token has already been used. Each token can only be used once to create a source.

You do use the token twice.

First, when creating the customer. Second, when trying to charge the card.

Instead, you can create a customer and and then pass $customer->id to Stripe 
when you create the charge:

$charge = \Stripe\Charge::create(array(
  "amount" => 1000, // amount in cents, again
  "currency" => "cad",
  "customer" => $customer->id,
  "description" => "Example charge")
);