Knack looping with Safari


I need your help because I don't get much help on this so far from Knack.

I have an application built on Knack, I'm using the embed code in a nginx redirected URL or proxy because I don't want my clients see that we use Knack.

Everything is fine except that when we use Safari, the APP is looping and apparently it is because of the cookies.

Do you have any recommendations to solve this ?

In fact, we are using this example

location /portal {
proxy_set_header X-Real-IP $remote_addr;