Mobile Menu Doesn't Work & can't update plugins

the mobile menu on my website doesn’t work. It won’t open when you click on the menu icon. In the inspect element i do get this error which may be the culprit.

Uncaught TypeError: Cannot set property ‘device’ of undefined
at isIsIOS (scripts.js?ver=1.0.16:9)
at HTMLDocument.<anonymous> (scripts.js?ver=1.0.16:126)
at i (jquery.js:2)
at Object.fireWith [as resolveWith] (jquery.js:2)
at Function.ready (jquery.js:2)
at HTMLDocument.J (jquery.js:2)

The theme wants me to update my contact form but when i try i get this error as well: Update failed: The package could not be installed. PCLZIP_ERR_BAD_FORMAT (-10) : Unable to find End of Central Dir Record signature

Please advise. my website URL is

Hey there

Try to install this plugin for menu not working problem:

For the second problem check this solution: