MySQLi Update not submitting - triple checked everything - no errors, it's just not submitting!

I have five MySQLi Update behaviours on a single page, but they are triggered by different buttons so there's no conflict there.
The second of these isn't submitting. All the others do.

Page attached, or you can check this online at the following address. Please note that you'll need to complete Step 1 before you get to Step 2:
www.sportsmedicalcertificates.com/health-screening-form.php?tab1=1

Soooo confused. :(
Hoping that you'll spot the obvious mistake that I just can't see. Thank you.
NJ

It isn't submitting because you have validation on both the US and Metric versions of the form and only one is being filled out... which means the form doesn't pass validation and can't be submitted. You need to make the validation conditional so that if you choose Inches then the centimeters value isn't required and vice-versa.

Yes, I have a JS onChange function on the page that allows users to select either Feet/Inches or CM for height and either Kg or Lbs for weight.

I had every one of those fields set as required, so when one of the fields is hidden by the onChange event, it is still required because it is only being hidden, not disabled. This is what's preventing the form from submitting.

Making the validation conditional...I will give that a try but this is all getting beyond me a bit. Any good tutorials on that?

Hope you had a good break Ray.
Thanks for the support, as ever.
NJ

I'm still in the airport in Miami, but I'll be officially back tomorrow. Yes, conditional validation can be complicated. I don't have a tutorial on it. I'll show you how to do it for free in a premier support ticket if you will do a tutorial afterward.