lynx39/lara-pdf-merger not working on live ubuntu server Laravel

I am using this package https://packagist.org/packages/lynx39/lara-pdf-merger for merging pdfs. This package is working fine on localhost but not working on live server .

Giving this error

Exception
Symfony\Component\Debug\Exception\FatalThrowableError: Class 'TCPDI' not found in /var/www/html/coldxlogistics/vendor/daltcore/lara-pdf-merger/src/LynX39/LaraPdfMerger/PdfManage.php:19

What could be the reason?

via Chebli Mohamed