Stripe test card is declined

Hello all, not sure if you can assist. I thought I had done everything correctly, but evidently not.

1. I created the payment buttons for stripe. I added the short code to my web pages in wordpress.
2. I copied the test and live api keys and placed them inside the plugin.
3. I found the stripe test card numbers
4. I changed my website to https:// and made sure the payment pages definitely show https:// and they do.
5. I try to check out with the test card and it says card declined.

I am at a loss what I have done wrong and how to correct it. Please assist if you can.
I did a screencast of the issue so you can see what happens.

https://www.youtube.com/watch?v=vM3mUtaP2Dk