Checking available quantity [PRETASHOP 1.7.5.0]

[okz]

Hello,

I have a problem, As you can see on this GIF on a website I check, the stock is checked when you try to add or removes product in stock.

My problem is, on my website, NOTHING HAPPENS, look :

 

Then you can add 3000000 products if you want. I try so looking on the core file in Prestashop but nothing good.

Can you help me with this ?

more example :

Working :

 

 

My website (no working)

 

Edited December 1, 2020 by okz (see edit history)