Why the Error on some Browsers?

I don't know what's happening. But a lot of our clients are complaining about using the form. Sometimes it just doesn't upload. They see a white board, where they can't see the options So, they can't fill the form and send us. We are getting daily complaints. Sometimes it doesn't work With Google Chrome, others with Internet Explorer. I want to know when will this be over, because I can't spend the day telling clients to change the browser they are using. It's unacceptable.
Thanks for the attention. 

I'm not sure if changing browsers is the answer to the problem your users are encountering. I tried loading your page a number of times but I was not able to replicate the problem. If you get to encounter this problem again, can you share with us a screenshot of how it appears?  

Also, you can try replacing your code with an iframe code instead to see if the problem is about conflicts on javascript codes on your browser and on the form. Please check this guide to know how to get the said code on this guide: https://www.jotform.com/help/148-Getting-the-form-iFrame-code 

Please let us know if the problem persists.

Hello papag, 

I have inspected your page source and i noticed this

You embed the form using iframe, but the form's iframe is inside to another iframe. It is theoretically possible, but it may cause rendering problems sometimes.

I suggest you to change this structure, you can integrate the form without outer iframe.

I hope it helps