I can't either. Same error. The "customer service" is absolutely zero help. I got a long pause after I explained the error message, and then "Oh. There must be a problem with the website. Why don't you try in the morning?"
Other posts from earlier say that there were outages, but they've been cleared. Not buying it.
I'm having this issue as well... like Sprint doesn't think my money is good enough. WTH?
This is what I kept on getting every time I click "Pay Bill":
We take your account security seriously. To ensure that your information remains secure, you'll need to update your profile before you can view these details.
To do so, go to My preferences > All about my account > My account info and click Update or add another account.
I "saved" and even updated my pin and EVERYTHING! Paying Sprint "Online" has never been more inconvenient. Unacceptable!
I talked with our production support team and here is what the said:
There was a pay bill issues last night for just over an hour from 9 -10 PM CST that was addressed through a production ticket. Customers experienced latency and were unable to complete self-service transactions on Sprint.com. The experience that the customers blogged about was experienced during the outage. This has been resolved.