The discussion thread is here: http://www.airportcitygame.com/threads/how-to-subscribe.23173/ For once the subscription ads appeared and at the time I didn't know what it is and skipped it. Later on I realized that it is helpful and planned to subscribe but my subscription option is completely gone so that I couldn't subscribe at all. I contacted tech support a week ago but it wasn't useful. The response was slow and the information is useless. First the tech support asked me to clear cache and restart my pad. But I am using iPad and there is no clear cache option at all. Restarting didn't help of course. Second the tech support asked me to switch to a stable network. hmm.. This does not seem a serious option at all. My network is stable and switching didn't help either. I myself is a senior software engineer so I know what is reasonable and what is not... I asked to help to subscribe me first so that I don't need to wait while the developers are debugging the issue. I said I can pay for it but there is no response at all. I feel I am not alone and this might be a big issue as many people don't know the option to subscribe and you guys may lose revenue because of it.