Template not changing

Hi

i have copied index-pdf.php to my theme directory but whatever change i make im still getting same results.

Even if i delete all lines in file im still getting pdf printed when i go to /pdf/.

I tried changing the one index-pdf.php in plugin directory itself and still no luck in adding my own elements.

What am i doing wrong?

https://ww.wp.xz.cn/plugins/wp-pdf-templates/