I have observed a new issue from last couple of days. No of selected units for a particular products are not updated on the cart. Here are the steps to create the error.
I appreciate the context and video that you have included as that is very helpful! Did the coding change advised by @gr_trading , work for you? If so, be sure to mark their post as a solution to inform others that may view the thread.
Have you made any custom coding changes to the theme’s coding? I can confirm with you that the quantity is not displaying the correct amount when adding more than one of the same products.
Thank you so much for the solution but not a techie to make these changes. If you can tell me which file needs to change then I ask someone in my team to do so.
@Ollie I have not tried the earlier solution as no that technically skilled.