Hey Gilles,
This issue often happens when you send the whole token object in the `source` parameter instead of just sending the token id.
If you look into your logs in the dashboard [1], you should see your failed request as a POST /v1/charges. If you click on one of those, you'll see what you sent to our API and confirm what is passed in that parameter. It likely looks like `source: "{"id": "tok_123","....` instead of `source: "tok_123"`.
If that's the issue, you'll want to change your code sending the token to your server to ensure that you pass the token id and nothing else. You'll likely want `
result.token.id` instead of `result.token` and you can see an example here:
https://jsfiddle.net/edz9d5Ln/
If that's not the issue, our support team can look into your logs though and find out what's causing the bug. You can contact them here:
https://support.stripe.com/email
Hope this helps!
Remi