In-App-Purchase is gone! – AmpKit - Guitar amps & pedals Review

I enabled all the boxes and amps through In-App purchase several years ago. But all of a sudden, none of the purchased boxes and amps are enabled and I can’t use any of them. I contacted AmpKit and a support person (Kristina Lyamina) said they screwed up something and asked me the receipt. I mailed a copy of the receipt last month but nothing happened since then. No reply, no action on my repeated inquiries. What’s going on?
Review by 탈옥2012 on AmpKit - Guitar amps & pedals.