I sussed part of my issue, I was trying to login with email address but because I paid by Apple I need to sign in with that account .I have similar problems. My desktop works OK but my Android phone app is a mess. It keeps offering me a free trial when I am a member. I finally managed to sign in but my account details don't even have my name. Help requests not answered. Blog is confusing. No user guide that I can find. The desktop version is OK but says I have no subscriptions, but I have a receipt for payment. Maybe I just need to understand it all better but on the face of it, it appears to be a bit of a mess. Techy features seem to work - very good in fact.
If it helps when I ran planefinder on windows I eventually decided to select login via apple instead of using my email (which is the same for my apple setup) because I also had ads appearing and after putting some details in it requests a security code from apple which was sent to my phone to enter on my(windows) laptop because I originally used iOS to setup and pay through my apple account and the method of payment I have linked is the same and it works ok.I didn't even know I had paid by Apple until I had my credit card statement. I have 2 Apple iPads. The older one appears not to be compatible while the newer one does show the features I had paid for. My desktop (Windows 11) does not offer the new Plane Finder features I have paid for and continues to run the trial version - as does my Samsung Galaxy. Support requests have not even been acknowledged, let alone resolved. Maybe Proudfroot are having major support issues at present and I do not wish to exacerbate them, but at least give me what I paid for! The part of the package that does work OK is the income part. I just don't know how to make contact with them to sort it out. Any ideas?
Perhaps an honest Google review would chivvy things along a bit.