Fatal error: Uncaught Error: Call to undefined function wp_get_current_userError

Recived this error and I could not get into wordpress, I had to get my host provider to get in for me to dactivae Ultimate member to get in to do other tasks. How can I fix this error so I can start using Ultimate Member again?

Fatal error: Uncaught Error: Call to undefined function wp_get_current_user() in /hermes/bosnacweb08/bosnacweb08au/b1641/ipg.wgdavis66975/wp_site_1649001095/wp-includes/capabilities.php:693 Stack trace: #0 /hermes/bosnacweb08/bosnacweb08au/b1641/ipg.wgdavis66975/wp_site_1649001095/wp-content/plugins/ultimate-member/includes/core/class-access.php(512): current_user_can(‘administrator’) #1 /hermes/bosnacweb08/bosnacweb08au/b1641/ipg.wgdavis66975/wp_site_1649001095/wp-includes/class-wp-hook.php(307): um\core\Access->custom_count_posts_handler(Object(stdClass), ‘post’, ”) #2 /hermes/bosnacweb08/bosnacweb08au/b1641/ipg.wgdavis66975/wp_site_1649001095/wp-includes/plugin.php(189): WP_Hook->apply_filters(Object(stdClass), Array) #3 /hermes/bosnacweb08/bosnacweb08au/b1641/ipg.wgdavis66975/wp_site_1649001095/wp-includes/post.php(3082): apply_filters(‘wp_count_posts’, Object(stdClass), ‘post’, ”) #4 /hermes/bosnacweb08/bosnacweb08au/b1641/ipg.wgdavis66975/wp_site_1649001095/wp-content/plugins/wp-clone-by-wp-academy/modules/promoti in /hermes/bosnacweb08/bosnacweb08au/b1641/ipg.wgdavis66975/wp_site_1649001095/wp-includes/capabilities.php on line 693
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