RwandAir review: Online payment challenges

Good afternoon, Team!
My name is Prof. Kamya Deogratias and I am facing a problem of making an online payment for the ticket that I booked. I have tried all the payment methods available on your portal (rwandair.com) but at every attempt, I am faced with an apology of failure to process the payment despite the fact that there is enough money to pay using any of the available payment options.
Kindly advise how to proceed with an online payment since I am far from any Rwandair office.

Booking Reference: 9X6KE
Kindly waiting for your support
Prof. Kamya Deogratias
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