I have just implemented Stripe for payment processing within my application and everything seems okay, except one issue I just can't understand.

[I am using the test data listed here](https://stripe.com/docs/testing). Specifically, I send the following data:

![enter image description here](https://i.stack.imgur.com/r9Hdw.png)

![enter image description here](https://i.stack.imgur.com/hSThj.png)

The above two sets of data both fail:

![enter image description here](https://i.stack.imgur.com/1Pip5.png)

If I change the month to be `10`, `11` or `12`, it works okay.

This issue holds true for all other test card numbers as well.