Recheck users ticket purchases before submitting

previous support: http://www.jotform.com/answers/767296-How-to-change-functionality-of-Ticket-Purchase-widget-to-act-like-radio-button-field

So I am trying to get help with the widget ticket purchases 

It works perfectly but I am having one issue

is it possible to have the form, once the submit button is hit, to recheck the ticket purchases widget to make sure there spots are available before submitting 

reason being because, lets say there is one spot left in a class, but two users open the form at the same time, if the first user completes the form and submits, it should make the spot unavailable for the second user but for some reason the user is still able to submit the form with the sold out spot because it only updates if the form us refreshed or the form is opened after the submission is sent

so if you are on the form before it is submitted it acts as though there is still spots available which ends up over selling

so i need another check while to be made, while the form is being submitted on all user ticket purchases for each child 

so if a user signs only one child up it will only check the first child ticket purchases and make sure all spots are available

but if a user sign two children up ( up to 4 ) it will check all childs ticket purchases and make sure they are spots available for all , if not it mist throw some error

http://stackoverflow.com/questions/4249809/reload-an-iframe-with-jquery

We were looking at this, if someone can please help me implement this that would be great thanks    

here is a clone of my form thanks https://form.jotform.com/60387393890164

Please do not post multiple threads, this only causes you to go to the end of the queue, as the support staff works answering the oldest ones.

it was posting ?

I couldnt tell i didnt think it was going through 

can you delete my others one please and thanks