#! hashbang removed but pages won't reload

Hi,
I have a spreadshop embedded in my WordPress home page with a JavaScript code (custom HTML)

I used usePushState: true and pushStateBaseUrl: ‘/’ because I wanted the #! hashbang removed from all URLS.
#! hashbang is removed but pages only load once. whenever I try to reload a page or copy paste a link in a browser the only thing I get is the Wordpress header and the footer, the shop does not load. It seems that the first time a page is loaded, the code handles everyting but if I reload the page, the process is handled by Wordpress that does not know how to handle the URL.

I tried the Spreadshop plugin but it doesn’t work with the homepage (works for other pages).

I tried some settings in .htaccess but nothing worked. for instance:
RewriteEngine On
RewriteBase /
RewriteRule ^#!/(.*)$ /$1 [L,NC,R]

Is there a way to solve this problem?