Space required after the Public Identifier in Entity, line: 1

Getting the following errors… I can’t tell what to do from here.
Any thoughts?

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Warning: DOMDocument::loadXML() [domdocument.loadxml]: Space required after the Public Identifier in Entity, line: 1 in /home/safemd/public_html/wp-content/plugins/wp-cassify/classes/wp_cassify_plugin.php on line 833

Warning: DOMDocument::loadXML() [domdocument.loadxml]: SystemLiteral ” or ‘ expected in Entity, line: 1 in /home/safemd/public_html/wp-content/plugins/wp-cassify/classes/wp_cassify_plugin.php on line 833

Warning: DOMDocument::loadXML() [domdocument.loadxml]: SYSTEM or PUBLIC, the URI is missing in Entity, line: 1 in /home/safemd/public_html/wp-content/plugins/wp-cassify/classes/wp_cassify_plugin.php on line 833

Warning: DOMDocument::loadXML() [domdocument.loadxml]: Opening and ending tag mismatch: hr line 7 and body in Entity, line: 9 in /home/safemd/public_html/wp-content/plugins/wp-cassify/classes/wp_cassify_plugin.php on line 833

Warning: DOMDocument::loadXML() [domdocument.loadxml]: Opening and ending tag mismatch: body line 4 and html in Entity, line: 9 in /home/safemd/public_html/wp-content/plugins/wp-cassify/classes/wp_cassify_plugin.php on line 833

Warning: DOMDocument::loadXML() [domdocument.loadxml]: Premature end of data in tag html line 2 in Entity, line: 10 in /home/safemd/public_html/wp-content/plugins/wp-cassify/classes/wp_cassify_plugin.php on line 833

Warning: DOMXPath::query() [domxpath.query]: Undefined namespace prefix in /home/safemd/public_html/wp-content/plugins/wp-cassify/classes/wp_cassify_plugin.php on line 839

Warning: Invalid argument supplied for foreach() in /home/safemd/public_html/wp-content/plugins/wp-cassify/classes/wp_cassify_plugin.php on line 841

Warning: DOMXPath::query() [domxpath.query]: Undefined namespace prefix in /home/safemd/public_html/wp-content/plugins/wp-cassify/classes/wp_cassify_plugin.php on line 847
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