Cart Modal not shown after adding to cart

[front7]

Hi everyone,

this problem is going to make me bald.

AS the title says, the modal doest show up it just add the product to the cart but doesnt show anything.
the page is 
https://www.paylesscolombia.co/cb/tenis-y-zapatos-deportivo/6498-336629-womens-blash-camodad-skneaker-shoes.html
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I have another page from the same company but there it works fine
https://www.payless.cr/es/tenis-y-zapatos-deportivo/7605-339038-men_s_sunset_rieder_casual_shoes.html


I compared all the files between those two to see if i could spot the difference, but it wasn't the case.
I couldn't find anything on the custom.js neither.

they share the same data on the ps_shoppingcart.js and so 😭

What could it be?
at this point i thinking on a direct approach inserting the modal with js but there has to be another way

Thank you!