Error in log

Hello,

i have the following Errormessage in my Logs

2018-04-27 19:38:18 Error 78.xx.xx.xx 404 GET /wp-content/plugins/shiftnav-pro/custom/custom.css HTTP/1.1 http://studentenwerk-augsburg.de/essen-trinken/mensen-cafeterien/augsburg/uni-augsburg/cafebar-alte-cafeteria-universitaet-augsburg/ Mozilla/5.0 (iPhone; CPU iPhone OS 11_3 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/11.0 Mobile/15E148 Safari/604.1 27.0 K Apache-Zugriff

Please i need Urgent help. i’m a Pro User.

Regards Nico

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