I am making a website, on which candidates can apply for the competition. But, a candidate can only apply, if he has paid the registration fee. So, when a user clicks on APPLY button on the website, he is directed to the payment form of the PayStack website, when he will do the payment, he will be redirected to the registration page. So, my question is, how can I confirm, If the user has made the payment or not, and is eligible to apply. Needs help with this.
I am using PHP for backend
