Please avoid Uniontelecard. My friend recommended Viapin. So I googled it and Uniontelecard came up. I bought a card for $20. It did not work. I tried multiple call-ins, including the 800 and numbers in CA, NJ, etc. None worked. I called asking for a refund. They refused saying all sales are final.
Even before I used the card, they have this "authorization" procedure. They have to get your approval before charging your credit card. They do this by calling you. They charged my card without my authorization. In all, every time I called to complain, the operators were very unprofessional and rude. Basically spoke to you like they were on the street with you. I'm betting that their operators are prison inmates working the lines.
In all, I recommend avoiding Uniontelecard.