When your letters and results are mixed up as shown in the picture below the solution is resetting your font settings. You probably put the font setting on big letters the are now too big for in the app. Here is what you can do:

IPHONE:
- Go to Settings > Accessibility, then select Display & Text Size.
- Tap Larger Text for larger font options.
- Drag the slider to a smaller font size and test if it is all right now

SAMSUNG (android):
- Open your device's Settings app.
- Tap Accessibility, then tap Font size.
- Use the slider to smaller your font size and test if it is all right now