Alright so i got my solution updated to 2.6.1.0 because i saw a lot of people with issues with vouchers in the older versions, however this didnt solve my problem for some reason.

 protected void btnVoucher_Click(object sender, EventArgs e)
 {
      VoucherCode vc = VoucherCode.SingleOrDefault(x => x.Code == tbVoucher.Text) ?? new VoucherCode();
      UCommerce.Xslt.Library.AddVoucher(tbVoucher.Text);
 }

I used the VoucherCode just to check that it actually finds it and it does, but when i validate the voucher with this

bool voucherOK = VoucherCodes.All().Any(x => x.Code == tbVoucher.Text && x.MaxUses > x.NumberUsed && x.VoucherTarget.CampaignItem.Campaign.Enabled && x.VoucherTarget.CampaignItem.Campaign.StartsOn >= DateTime.Now && x.VoucherTarget.CampaignItem.Campaign.EndsOn >= DateTime.Now)

It doesent validate i've checked the parameters in the backend and everything should be alright, i even created a few new to test. They are enabled and they are within date limits. So i'm not really sure why its not doing anything and not sure why it doesent validate :/