Fatal Error

Hiya

My blog post pages are displaying in 1 container in the middle of the screen, comments section doesn’t show, and I keep getting a fatal error on my blog post pages:

Fatal error: Uncaught Error: Object of class WP_Comment could not be converted to string in /home3/wowjamwe/development.wowjamweb.com/wp-content/plugins/wp-user-manager/includes/admin/class-wpum-avatars.php:205 Stack trace: #0 /home3/wowjamwe/development.wowjamweb.com/wp-includes/class-wp-hook.php(308): WPUM_Avatars->set_default_avatar() #1 /home3/wowjamwe/development.wowjamweb.com/wp-includes/plugin.php(205): WP_Hook->apply_filters() #2 /home3/wowjamwe/development.wowjamweb.com/wp-includes/link-template.php(4503): apply_filters() #3 /home3/wowjamwe/development.wowjamweb.com/wp-includes/link-template.php(4271): get_avatar_data() #4 /home3/wowjamwe/development.wowjamweb.com/wp-includes/pluggable.php(2871): get_avatar_url() #5 /home3/wowjamwe/development.wowjamweb.com/wp-content/themes/astra/inc/blog/single-blog.php(118): get_avatar() #6 /home3/wowjamwe/development.wowjamweb.com/wp-includes/class-walker-comment.php(184): astra_theme_comment() #7 /home3/wowjamwe/development.wowjamweb.com/wp-includes/class-wp-walker.php(147): Walker_Comment->start_el() #8 /home3/wowjamwe/development.wowjamweb.com/wp-includes/class-walker-comment.php(139): Walker->display_element() #9 /home3/wowjamwe/development.wowjamweb.com/wp-includes/class-wp-walker.php(390): Walker_Comment->display_element() #10 /home3/wowjamwe/development.wowjamweb.com/wp-includes/comment-template.php(2346): Walker->paged_walk() #11 /home3/wowjamwe/development.wowjamweb.com/wp-content/themes/astra/comments.php(70): wp_list_comments() #12 /home3/wowjamwe/development.wowjamweb.com/wp-includes/comment-template.php(1593): require('/home3/wowjamwe...') #13 /home3/wowjamwe/development.wowjamweb.com/wp-content/themes/astra-child/single.php(39): comments_template() #14 /home3/wowjamwe/development.wowjamweb.com/wp-includes/template-loader.php(106): include('/home3/wowjamwe...') #15 /home3/wowjamwe/development.wowjamweb.com/wp-blog-header.php(19): require_once('/home3/wowjamwe...') #16 /home3/wowjamwe/development.wowjamweb.com/index.php(17): require('/home3/wowjamwe...') #17 {main} thrown in?/home3/wowjamwe/development.wowjamweb.com/wp-content/plugins/wp-user-manager/includes/admin/class-wpum-avatars.php?on line?205

When I disable WPUM it fixes all of these issues. Can I get some help on how to solve this please?

Thanks.

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