mpdf : WriteHTML not working for morethan 10 array with css and image

Question

we are using more html dynamic value and image urls and style.css also it was working fine earlier but after the pathches upgrade in server not working not throwing any error also application will hang

here pdfcontent is having more that 15 arrays

$this->m_pdf->pdf->WriteHTML($pdfcontent[$i], \Mpdf\HTMLParserMode::HTML_BODY);

after this code application will hang