Can't pay mr price due to website issues

The payment options on the website aren't working. I sent email requesting help or advice and just got automated responses that didn't solve my problem.

My bank card expired and I need to add a new card to use for payment but when I click add new card it tries to go onto secureacceptance.cybersource.com/pay but the page ALWAYS times out. Same with the EFT option.

I can't go in store to pay, what am I supposed to do now?