Unaccptable Service

I had purchased a few vouchers from Hyperli. I attempted using the a voucher over the weekend and was denied at the restaurant saying it had expired. The expiry date on the voucher states 05.01.2018. I have sent e-mails from Monday to Hyperli, not a response or call. The worst is that there is no contact numbers for you to call them. This is so unprofessional. Are they ******** customers? I will no longer be purchasing from this website and will caution you as well. They do not operate nearly as professionally as Groupon so don't be taken for a ride.