Fatal error for sitemap index

Hi,

When i open my sitemap index: http://www.envergure-coaching.com/sitemap_index.xml, i have fatal error ! Why ?

Fatal error: Uncaught Error: Class ‘RankMath\Frontend\Frontend’ not found in C:\HostingSpaces\envergur\envergure-coaching.com\wwwroot\wp-content\plugins\seo-by-rank-math\rank-math.php:353 Stack trace: #0 C:\HostingSpaces\envergur\envergure-coaching.com\wwwroot\wp-includes\class-wp-hook.php(286): RankMath->init_frontend(”) #1 C:\HostingSpaces\envergur\envergure-coaching.com\wwwroot\wp-includes\class-wp-hook.php(310): WP_Hook->apply_filters(NULL, Array) #2 C:\HostingSpaces\envergur\envergure-coaching.com\wwwroot\wp-includes\plugin.php(465): WP_Hook->do_action(Array) #3 C:\HostingSpaces\envergur\envergure-coaching.com\wwwroot\wp-settings.php(374): do_action(‘plugins_loaded’) #4 C:\HostingSpaces\envergur\envergure-coaching.com\wwwroot\wp-config.php(90): require_once(‘C:\\HostingSpace…’) #5 C:\HostingSpaces\envergur\envergure-coaching.com\wwwroot\wp-load.php(37): require_once(‘C:\\HostingSpace…’) #6 C:\HostingSpaces\envergur\envergure-coaching.com\wwwroot\wp-blog-header.php(13): require_once(‘C:\\HostingSpace…’) #7 C:\H in C:\HostingSpaces\envergur\envergure-coaching.com\wwwroot\wp-content\plugins\seo-by-rank-math\rank-math.php on line 353

Can you check please ?

Thank you in advance !

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