XML Sitemap or ALL In One SEO issue

Hi, I have installed XML Sitemap and All in one SEO plugins in my wordpress and I am using the title of the blogs for the url’s.
Up to there all works fine.

The URL’s look like this:

https://mysite.com/blog/post-title-example/

No, for some reason Google is looking for:

https://mysite.com/blog/post-title-example/index.php although nothing that I know of is telling it to look for the extra index.php

So, google is reporting errors :o(

Is there any setting that I might have missed? Where is it getting the extra index.php? Why is it looking for it when the links don’t use it?

Anyone has any idea of what the problem might be please?

Thanks

stevensatch