It has now been almost a month since PHP 7.0 has reached "end-of-life" (EOL) status. Please do not use PHP 7.0 any more as it's no longer supported and will be vulnerable to new security issues or lacking newer bug fixes. This should also be a red flag for you to avoid any themes or plugins that are not compatible with newer PHP versions (PHP 7.1, 7.2, and upcoming 7.3).
Again, please upgrade
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