It happened to me too, but I paid for the app on google store and the payment information (from months ago) disappeared. As if I have not purchase the app at all, or if the app did not existed. So Google Support said they can't help with it.
This happened to me as well. I paid for the Calculator to use it for conversions and dietary law requirements. I say woe to Google and HP for making it mysteriously disappear. It is time to involve the State attorney General and each state follows its own version of the Uniform Commercial Code which governs purchases like these so I can send a demand letter certified mail and if it is not paid then I can enlist California's Attorney generals Offices help to get it paid. It is the act of acting like a giant company and insulting the little guy that I detest.