Your current code should have worked. The only way I could get it to fail on my end was by adding empty characters, like this:
<fieldset>
<label>Enter Your First Name: <input /></label> <!--10 empty char before input tag-->
<label>Enter Your Last Name: <input /></label>
<label>Enter Your Email: <input /></label>
<label>Create a New Password: <input /></label>
</fieldset>
I was having the same issue for step 16 (looks like the step might’ve moved to the right one. I was able to get it to work on my phone though. Thanks for the info!