OP, nobody here thinks any of this is your fault, OS should be on the hook for this, as others have also said OS ‘customer service’ is not fit for purpose, the real issue here is Austria, which lets them get away with this kind of sharp practise, as mentioned previously, in the UK these kind of claims are entirely online, cost effective & UK consumer legislation is very strong & supportive of the consumer, here in FT, we can only advise, maybe best to take your angst out on the Austrian authorities for not providing a simple, swift & cost effective remedy ?