Error Message Appears Above Contact Form

Here’s what I see each time I add a contact form to a page:

Warning: strpos() expects parameter 1 to be string, array given in /home4/crissie/public_html/wp-includes/shortcodes.php on line 193

That error message appears in both the WP page editor and on the actual page that displays to the public. WHY?

See this page for the error message:

https://mshumblewordsmith.com/home-of-high-quality-content/about-me/