Warning: Undefined array key "printTxt" in /var/www/html/wp-content/themes/twentytwentyfive/pdf_lib/index.php on line 4

Fatal error: Uncaught Mpdf\MpdfException: Data has already been sent to output (/var/www/html/wp-content/themes/twentytwentyfive/pdf_lib/index.php at line 4), unable to output PDF file in /var/www/html/wp-content/themes/twentytwentyfive/pdf_lib/src/Mpdf.php:9572
Stack trace:
#0 /var/www/html/wp-content/themes/twentytwentyfive/pdf_lib/index.php(51): Mpdf\Mpdf->Output()
#1 /var/www/html/wp-content/themes/twentytwentyfive/page-personalai_pdf.php(3): require_once('/var/www/html/w...')
#2 /var/www/html/wp-includes/template-loader.php(106): include('/var/www/html/w...')
#3 /var/www/html/wp-blog-header.php(19): require_once('/var/www/html/w...')
#4 /var/www/html/index.php(17): require('/var/www/html/w...')
#5 {main}
  thrown in /var/www/html/wp-content/themes/twentytwentyfive/pdf_lib/src/Mpdf.php on line 9572