URL includes unwanted /index.php/ ?

Hi,

I have a newly deployed laravel site (with apache on heroku).

I notice in the logs that some users access it via: <my site url>/index.php/<rest of the path>

Whereas for most it is: <my site url>/<rest of the path> (i.e., what I would call normal, & expect)

Why could this be? I think I'd like to switch it off if possible.

Google bot accessed it using the /index.php/ insertion, too.... (I think both with and without)

Thanks for any help. Curious...

I'm just using default laravel settings as far as I know (5.3).