@Zagala_97 Again, as mentioned previously it’s not up to the developer to delete records of your purchases, or ask for payment again, apple handles purchases, if you’re facing this issue, you must contact Apple.
Also, the price for Marvis was lower in 2022 than it is now.
@sagginghingepin@hausravenclaw Marvis plays music via Apple Music app, so you can play music via Marvis but use the Apple Music app for Sing. Apple has kept the sing to themselves and have not exposed it to the developers.