Crushed website after setup API

Hi, I tested your plugin on a staging environment, everything is ok, and we activated the plugin on the live version of the site https://turnkeystaffing.com/ and my colleague paid for the Pro version. But after adding the API and saving these settings, the site died. This is the error. I have now uninstalled the plugin to figure out what the problem is. Perhaps the problem is in my version of the VP or a conflict with other plugins?

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