? Older Entries link error (someone please help me with this T_T)

Hi, my wordpress blog is at https://www.amosatlantis.com

Scroll to the bottom of the page, and there will be this
? Older Entries link.

However, there is some error with the link. It leads to https://www.amosatlantis.com/index.php/Index.php/page/2/

Notice there is another Index.php in the link. I use a custom permalink structure that is /index.php/%postname%/

Can anyone help me out and resolve the problem for me about the extra Index.php in the ? Older Entries link and from which file can I fix it?

Thank a million!