Pagination arrows don't work

Hi! The "previous" and "next" arrows of the products pagination don't work properly.

These arrows only work until the page number 2. Starting at 2, doesn't go to the third page of products...

Here's an link where you can test it: http://saintmara.es/es/91-abrigos-coats-jackets#

Thanks for your attention and I keep waiting for your response.