Update - Jan 14, 2023
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Finally found the solution which works without needing any file replacement or any advanced steps (thanks to our friend response Nawres). Follow the steps below:
Before I continue to explain the steps, if you have changed your core.js file or you have replaced it with older versions (e.g. PS1.7.7.x, etc) remove it and upload the original core.js file which is within default PrestaShop file (exact the same with your PS version) then follow the rest of instructions.
Step 1: Open your core.js file which is inside your themes directory and edit it.
Step 2: Search for code below:
o.default.cart=e.resp.cart;
And replace it with:
o.default.cart=e.reason.cart;
Step 3: Reset your ps_shoppingcart module from your BO -> Modules.
Step 4: Go to your BO -> Advanced Parameters -> and click on Clear Cache button.
Step 5: Go to your store front-office, press Ctrl+Shift+R (or ⌘+shift+R on mac) to refresh your browser cookies.
You're done!