Trouble running est

Tell us what’s happening:
Hi Everyone. Last night I created an account here and did some completed a few challenges on my tablet. I tried to use my laptop but I found not run test after completing the challenge. I tried to delete my account and start over but had no luck running the test again. So I am not sure if there is a problem with switching between my laptop and tablet, the browser or if something else is wrong. Any help is much appreciated.

Your code so far

<h1>Hello World</h1>

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.140 Safari/537.36 Edge/17.17134.

Link to the challenge:

If you are in IE or Edge or Safari, then it is not gonna work, use Chrome as first choice and Firefox also works well in latest version.

Yes. Thanks. Working in Firefox.