test submission successful but fields not in DB setup

[mrGarvin]

(I assume you have replaced the "real life" URL to the external form with 127.0.0.1 for this example? Right?)
The only thing I can see is that you're not using the standard "name giving" attribute on your inputs. You just use "id". Don't know if this is important, but it might be a problem...

So, this:

Code:

<input type="text" placeholder="Name" required="" id="username">

should be:

Code:

<input type="text" placeholder="Name" required="" id="username" name="username">

And at the end you're using the button tag instead of the input type=button.

Maybe this throws it off? No expert here... but these are the only issues I can spot.