Function add_theme_support( ‘html5’ ) was called incorrectly how to solve this

Hi there! I am getting errors on my site after activating the new theme. For my website, I used Astra now I’ve switched to the contentberg theme. After Installing that theme I am facing some errors like : Notice: Function add_theme_support( ‘html5’ ) was called incorrectly. You need to pass an array of types. Please see Debugging in WordPress for more information. (This message was added in version 3.6.1.) in /home/theuniqu/public_html/wp-includes/functions.php on line 5835

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