Misleading communication and a way to remove a voucher that was given as an apology

After holster was unable to deliver a purchase from Black Friday I received an email saying that they would hold my payment as a credit (or I could choose a refund) PLUS I would receive a voucher for 50% off my next purchase . However I hadn’t bought shoes since the Black Friday and now that I do want to purchase shoes I have been told the voucher has expired , my email did not state an expiry date nor did it tell me to check my account on their website. Now when I phoned them they tell me I should have checked my account . Why would I randomly check my account to “check” the voucher when I don’t intend buying anything. Basically it’s poor customer service , why should the voucher expire and if it did that should have been stated in my email and this was not the case . Be wary of communication from holster it’s misleading and dishonest . If you want excellent customer service deal with a company like saint and summer ! I am not a difficult customer but if something is wrong it’s wrong and just honour what you write to your customers .