Hi @anxirileyrhsuqv, thanks for reaching out.
Is this still an issue for you? We took a look at the app on Thunkable Live but the language settings page does not seem to be crashing the app.
If it is, one place to look is at your conditionals and do some debugging to test those and ensure that they are returning null values–this can cause a mobile app to crash but is sometimes handled better on the web.
There is a great post by our Power User Tatian about how to best debug in Thunkable. Take a look and let us know what you find!