In the sentence "The highest number you can pick is " The last 2 letters of the word THE has a red line under them, I noticed it on your screen while watching as well, the only difference is it wont go away on mine and apparently is registering it as an error, I’m very unsure about how to fix it and it wont let me continue in til it is.
Is this still an issue for you? If so, can you pop a screenshot up please.
Can you show us what the error message/number is?