I'm unable to refill my phone on the Straight Talk website.

I've had Straight Talk for probably a decade or so and have been paying it online without issue for years. I've always done it as a guest, too. I've never had an account set up.

Since my payment is due, I went to the website and an Imperva page popped up to check if I was human as it said my computer flagged for potential malware? When I finished with that, I went to refill my phone, but when I went to put in my number and press the verification that I'm not a robot, I got an error message saying that it's unable to process it at this time.

I've tried on my phone and another browser and it's the same issue each time. Is it just my luck or is the website having issues with refills?