i hope you can reply , i came from different game and it's VN game but i did as you said and it didn't work , most of the devs i asked didn't answer probably busy with their life , one of them actually answered and i better redirect it to you so you can understand better , i even sent a post , hope it doesn't get blocked . 

https://itch.io/post/9231097

if you hopefully were able to answer me i'll be able to provide you with much details , thank you in advance .

If you want reset or delete your save data 

Clear data the app or delete the file