Peramlinks problem showing index.php with every post

One of the categories of our site has been on wordpress https://bookmyhotel.biz/travelnews, I have seen the permalinks of it shows the bothering index.php link with every URL i.e. https://bookmyhotel.biz/travelnews/index.php/from-vineyards-of-styria-to-the-julian-alps-book-package-tour-to-slovenia/

Is there a way that the bothering word “index.php” should not come in every URL. I have tried all URLs mentioned in “Permalinks” section in Admin but it shows 404 error.

Thanks for your time.