Fatal error: Uncaught typeError

Fatal error: Uncaught TypeError: Argument 1 passed to wp_register_font_collection() must be of the type string, array given, called in /home/customer/www/singelwandelaars.be/public_html/wp-content/plugins/gutenberg/lib/experimental/fonts/font-library/font-library.php on line 136 and defined in /home/customer/www/singelwandelaars.be/public_html/wp-includes/fonts.php:78 Stack trace: #0 /home/customer/www/singelwandelaars.be/public_html/wp-content/plugins/gutenberg/lib/experimental/fonts/font-library/font-library.php(136): wp_register_font_collection(Array) #1 /home/customer/www/singelwandelaars.be/public_html/wp-content/plugins/gutenberg/lib/load.php(146): require('/home/customer/...') #2 /home/customer/www/singelwandelaars.be/public_html/wp-content/plugins/gutenberg/gutenberg.php(73): require_once('/home/customer/...') #3 /home/customer/www/singelwandelaars.be/public_html/wp-content/plugins/gutenberg/gutenberg.php(20): gutenberg_pre_init() #4 /home/customer/www/singelwandelaars.be/public_html/wp-settings.php(517): include_ in /home/customer/www/singelwandelaars.be/public_html/wp-includes/fonts.php on line 78

Dear,

It′s been several weeks that our website doesn′t work due to this fatal error. I′ve updated themes and plugins but that doesn′t seem to work. I also deleted the gutenberg plugin.

Does anyone has an idea what I can do about this?

many thanks!