start Date could not be converted to date object.Check date and global timezone.

bool(false) object(DateTimeZone)#1126 (2) { ["timezone_type"]=> int(3) ["timezone"]=> string(16) "Europe/Stockholm" } Fatal error: Uncaught TypeError: date_modify(): Argument #1 ($object) must be of type DateTime, bool given in /customers/9/3/5/ejjk.com/httpd.www/v2/wp-content/plugins/amr-ical-events-list/includes/amr-ical-events-list-main.php:2091 Stack trace: #0 /customers/9/3/5/ejjk.com/httpd.www/v2/wp-content/plugins/amr-ical-events-list/includes/amr-ical-events-list-main.php(2091): date_modify(false, '-507860000 days') #1 /customers/9/3/5/ejjk.com/httpd.www/v2/wp-content/plugins/amr-ical-events-list/includes/amr-ical-events-list-main.php(2209): amr_GET_params(Array) #2 /customers/9/3/5/ejjk.com/httpd.www/v2/wp-includes/shortcodes.php(434): amr_do_ical_shortcode(Array, '', 'iCal') #3 [internal function]: do_shortcode_tag(Array) #4 /customers/9/3/5/ejjk.com/httpd.www/v2/wp-includes/shortcodes.php(273): preg_replace_callback('/\\[(\\[?)(iCal)(...', 'do_shortcode_ta...', '

Kommande h\xC3\xA4...') #5 /customers/9/3/5/ejjk.com/httpd.www/v2/wp-includes/class-wp-hook.php(324): do_shortcode('

Kommande h\xC3\xA4...') #6 /customers/9/3/5/ejjk.com/httpd.www/v2/wp-includes/plugin.php(205): WP_Hook->apply_filters('

Kommande h\xC3\xA4...', Array) #7 /customers/9/3/5/ejjk.com/httpd.www/v2/wp-includes/post-template.php(256): apply_filters('the_content', 'Kommande h\xC3\xA4nde...') #8 /customers/9/3/5/ejjk.com/httpd.www/v2/wp-content/themes/baskerville/page.php(50): the_content() #9 /customers/9/3/5/ejjk.com/httpd.www/v2/wp-includes/template-loader.php(106): include('/customers/9/3/...') #10 /customers/9/3/5/ejjk.com/httpd.www/v2/wp-blog-header.php(19): require_once('/customers/9/3/...') #11 /customers/9/3/5/ejjk.com/httpd.www/index.php(17): require('/customers/9/3/...') #12 {main} thrown in /customers/9/3/5/ejjk.com/httpd.www/v2/wp-content/plugins/amr-ical-events-list/includes/amr-ical-events-list-main.php on line 2091