Product Landing Page: Test-script bug?

I have completed the first 12 challenges, but when it comes to the navbar (user story #13) I write in css “position: fixed” and, suddenly, as you can see in the image, the test tool starts to display “Testing 1/16”.
Can someone help me?
Thanks and sorry for my bad english.

Had the same problem when I did it, try another browser and see if that works

In Firefox doesn’t work…In Edge the same problem…hoveverCattura1
Other solutions?