Vodabucks technical issues no communication , no remorse

I am disappointed at the vodabucks and vodastore service offering on the store has technical difficulties. I claimed a voucher using my vodabucks I waited for over 30 minutes and eventually paid with my own money and thought to check back when I get the chance. When I eventually wanted to use it apparently the coupon had been issued been consequently expired. I thought I would let it slide. I tried purchasing a Spur Voucher and the system would not allow me. I understand technical difficulties do exist, but I feel it necessary to inform clients ahead of time to manage expectations. I called the call center to highlight the 2 problems and the agent said I should have not waited to see that the coupon expired. Like I must make it my business to make sure the coupon doesn't expire, I was frustrated and in trying to share my frustration she told me I am not listening to her, I calmed down and listened but ultimately, I don't think my concerns were taken into consideration. I am not a keen customer anymore.