Sudoku Extreme funktioniert nicht

Fill the empty cells with numbers 1-9 in a way that each row, column and block (3x3 cells) only contains a single instance of the number 1-9. - 6 levels - beginner, easy, medium, hard, unfair and extreme. - It is highly customizable with many beautiful themes as well as settings to customize the app exactly the way you like it.  Manually filling notes also gets you extra points! - The quick fill feature lets you tap-and-hold a number and then simply tap cells and it will fill it with that number. - Numbers show how many instances of that number are left to be filled in the puzzle.  App comes with both light and dark amoled themes to be comfortable on your eyes! - The simple to use notes and hint features help you if you get stuck but we encourage spending time trying to figure out the puzzles without using hints.  Each higher level gives twice the number of points as the previous level. - Game can be paused and you can resume the previous game when you come back. - Sudoku Extreme can automatically pre-fill the notes and auto-remove them when they are used in a row, column or block.  Note that each mistake deducts points from your overall score. - After a game is finished, you get your overall stats like total time spent, best time, average time, overall score, hints used, mistakes made etc.  This can be used in Excel. - Advanced levels, Themes & Settings customization are part of a small one time only in app purchase. No subscriptions. No ads.  Cells filled with use of hints don't get any points. - Haptic feature gives a positive vibration when correct and negative vibration when wrong answer is filled.  Sudoku Extreme also comes with a graph of how your scores progress over time.  Sudoku Extreme is a beautiful way to experience classic Sudoku puzzles for both beginners & advanced players!  It's a great way to keep your mind active while relaxing to pass time.  Though we encourage disabling this setting and filling it manually as it makes your brain more active!  I offer a beautiful app free of ads, subscriptions, trackers and analytics for the absolute best experience for my users.  Your job is to fill the remaining empty cells.  The puzzle comes with a few cells pre-filled.  If you are enjoying the puzzles, please leave me a positive rating on the app store as that helps get the word out to others!  This can be disabled in settings. - If you make a mistake you can use the undo, delete and redo buttons.