Portoflio view all

Hi,

I have a problem with my page “portfolio” it doesnt show all the posts created- it doesnt make any change when I set to “view all”.
I just see 9 posts instead of the 12 posts I have so far.
Is there a way I can see all the posts in this section?

What I ‘ve done is go to them-options/portfolio-options/set items per page “-1”

https://theartoftravelblog.com/tipsandtricks/

I leave you my admin codes just in case:

https://theartoftravelblog.com/wp-admin
user: acportfolio
password: GTg%qb(RIVew2@Fs(Y&4xEYH

Thnak you so much in advance!!
Axi