FNB eBucks udemy courses not allowing me to sign up

FNB offers free Udemy courses, as part of the eBucks program with access to up to 6 courses per year.

I've been trying to sign up for a course for the past 2 weeks now and every single time I get to the payment section, it gives me an error. I've tried to use my credit card, cheque card and ebucks account as a payment method and it keeps failing. I contacted the secure chat, only to be told they cannot assist me and that I need to contact the eBucks customer service. The number given and stated on the internet doesn't even work!

Please FNB, this isn't acceptable.