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Unfortunately, I wasn't able to replicate your issue. I tried checking your webpage where the form is embedded and the form is not flickering.
It is working properly when I tested it using Google Chrome, Mozilla Firefox, and Internet Explorer 8.
Please try going to your direct form URL (http://www.jotform.me/form/52771867494471) and see if the form is flickering. If not, then it means that the problem happens if the form is embedded on the webpage. Please try re-embedding the form using Iframe method.
If it is still the same, please try another browser to see if that works.
Let us know if you're still having issues with it. Thank you.