I have to be at the presentation with my partner but I can't use the voucher?!?!?!?!?

I made a booking with One Year Gift only to be told the day before I was supposed to leave that I could not use the voucher because it is in my husband's name. My husband was planning on going with us but had to cancel last minute due to work. I spent Monday morning trying to sort it out to no avail. One Year Gift is completely adamant that you can't receive a voucher if you don't attend the presentation without your spouse but I'm not allowed to use the voucher? I was at the presentation, we have the same surname and I have a marriage certificate. It's as much my voucher as it is his. Please amend your terms and conditions, One Year Gift because it is completely ridiculous to send people away from presentations for coming alone but not allowing the partner to use the voucher. I'm very disappointed and so are my children.