Premium features disappeared after changing device

I have bought a yearly premium subscription on an app called Meitu in January 2022. My phone has been damaged in July the same year and after downloading the app onto a new device, the subscription is gone and apple doesn’t recognise I bought anything from this app. I do have a proof of payment and paid £26.99 for this… What should I do? There’s no way to contact the developers of the app, their website is in Chinese.