Conflict with Forminator plugin

Hi,
Use Hueman Version: 3.7.3
Unfortunately through the Forminator plugin, I found that the digital signature field of the Forminator form has problems
I went crazy to understand why this was happening.
After clearing the browser cache, the Cloudflare cache, and testing the module on different PCs and browsers, I disabled all plugins and enabled the default “Twenty Eleven” WP theme. With this everything works perfectly.
From the support of the plugin they say the problem is in the theme.
Could someone who knows Hueman theme well advise me what to do?
https://www.fiomasti.it/prova/
https://prnt.sc/xzjq4p
https://prnt.sc/xzjtap
https://prnt.sc/xzjwlq
thank you

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