Undefined Index Error on Home Page

Hello, I am receiving a header error on the home page of my Wordpress site stating the following: <b>Notice</b>: Undefined index: featured_content_button_text_4 in <b>/home1/departur/public_html/wp-content/themes/rock-star-pro/inc/featured-slider.php</b> on line <b>412</b> It states the same thing for button text 3, 4, 5, and 6 I'd include a screenshot, but cannot attach one here.. Not sure what is wrong here as I'm not including any button text features for the slider on the top of the page...The issue is not there every time. But once it pops up, it won't go away after a refresh. I checked the theme settings, but can't see anything immediately obvious...Please advise... URL: https://thejourneytributeband.com