http request on SSL secured page

Hello, i setup my multisite to take PayPal payments for the Pro Sites plugin, it is all configured like it should, but i am getting the following message when clicking the “PayPal Checkout” Button on the Pro Site Upgrade page /pro-site :

This is a non-secure form.

This form will be sent in a way that is not secure. Are you sure you want to send it?

I located the http request and it seems to be inside the <div id=”gateways-1″ class=”gateway gateway-primary”> … the form with the id=”paypal-payment-form”

Changing the link inside the tag from http to https trough Google Chromes Developers Tool allowed me to submit the form…

Unfortunately this is as far as i can go, could you please add the https to the plugin to avoid this kind of problems? It’s preventing me to use PayPal.

I will submit a link with the Support Access

Thanks for the support