[Rank Math SEO Plugin] Two Error Messages

[fledge007]

Hello

I have finally installed Rank Math on to my website.

However, I received these two error messages:

Warning: call_user_func_array() expects parameter 1 to be a valid callback, function 'wpfresh4_filter_robots' not found or invalid function name in /home3/fledge007/public_html/wp-includes/class-wp-hook.php on line 286

Warning: Cannot modify header information - headers already sent by (output started at /home3/fledge007/public_html/wp-includes/class-wp-hook.php:286) in /home3/fledge007/public_html/wp-admin/includes/misc.php on line 1126

My site is hosted by Hostgator

Wordpress ver:  4.9.8

The site is in an early stage of setup.

The plugins that are installed:

Akismet Anti-Spam

Contact Form 7

Easy Digital Downloads

InstaBuilder 2.0  (Activated)

MailOptin - Lite

MailPoet 3

Mesmerize Companion  (Activated)  Goes with the Mesmerize theme

One Click Demo Import  (Activated)

Rank Math SEO (Activated)

ThirstyAffiliates

UpdraftPlus - Backup/Restore

W3 Total Cache

Webcraftic Clearfy

WP Freshstart 4 (Activated)

WP-Optimize

WPForms Lite

Most of these plugins are installed for test purposes only.

Thank You,

James Plunkett

[Montgomerie]

Hello,

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