It due to the Isotope layout used on this projects page in which if the item (in this case is item 2 in your screenshot) occupy less space (in height), the next item will fullfill in that place and that's why item 3 showed there.
I temporarily disabled this Isotope layout in template settings so it can display in normal order as you wish:
![](https://www.joomlart.com/forums/assets/files/2024-04-08/1712558960-842603-screenshot-2024-04-08-at-14516-pm.png)
Kindly check.