'Bold Text Getting Duplicated in PDF to PPT Conversion for both ConvertApi and Adobe API

When I convert a PDF having bold text to PPT using ConvertApi or AdobeApi it gets duplicated. and I still could not find out the reason. To generate the PDF we can do CTRL+P and to convert it into PPT I am using this link https://www.adobe.com/in/acrobat/online/pdf-to-ppt.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        @font-face {
            font-family: 'Helvetica';
            src: url('./fonts/Helvetica.ttf') format('truetype');
        }
    </style>
</head>
<body>
    <div style="z-index:100;font-family: 'Helvetica';font-weight:bold;font-size: 10vh;">Hello World</div>
</body>
</html>

Result - enter image description here