Unfortunately for this kind of feature our hands are tied here as this is a server level function. We have no way of knowing what is correct or incorrect for your particular server. It could be one of twenty issues. All we can do is tell you how to configure it, but issues like that almost need to be worked out by the user. I wish I could tell you to do X, Y or Z, but it is not that easy when it comes to MySQL.

http://184.168.83.52/~homefitn/contact-us.php

Who's your host?

Is the width of the form supposed to be wider than it's showing on the page? If so it could be that you're CSS is clashing with a CSS tag in the Form code, or it could be that you put it into a space in your site that is not given a large enough width and it's conforming to the size it was put into. There truly are quite a few variables that make a difference with this, but hopefully you'll get it worked out as it shouldn't be too difficult to find the problem. The main thing to know here is that the width really "does" work just fine with Form Builder, so it's most likely due to the location you are putting it in the page and the settings of that location that are messing it up.

I think their issue is with mysql.

Was a responsive template used? The form width is 100%, rather than a pixel amount.
Just checked it again... Seems to be fine (width is still 100%, but with a max-width specified).