Question about pagination on CI3

everything seems to be working right now but not with page number 1. CI pagination ignore everything after the second segment on page 1 like this

Code:

1 = http://example.com/test/page/1
2 = http://example.com/test/page/2/category/item_id
3 = http://example.com/test/page/3/category/item_id
4 = http://example.com/test/page/4/category/item_id

that means the user can't go back to see items on the requested category on page 1

Correction: page number 1 can be set using

Code:

$config['first_url'] = base_url().'test/page/1'.$addittional_variables.$this->config->item('url_suffix');

so now I can have

Code:

http://example.com/test/page/1/category/item_id