Other questions

Locally saved internet cache files can sometimes lead to unexpected behavior in the product, info-flowstateco. 

When I enabled the track inventory setting, I was able to add the quantity of product when I replicated it on my end. This might be due to a problem with your browser.  

QuickBooks Online stops working properly because your browser is overloaded with site data. To see if the problem is with your browser, open QuickBooks in a private or incognito window. This can help us remove any cache-related issues that may have contributed to the problems. To access it, use the following shortcut keys: 

• Google Chrome: Press CTRL + Shift + N.
• Safari: Press Command + Shift + N.
• Mozilla Firefox: Press CTRL + Shift + P.  

If the steps above work, I suggest clearing your browser's cache to boost browser-related issues. Some stored data on your browser can impact the data being transmitted, thus causing some unusual responses. 

In case private browsing doesn't work, I'd recommend using different browsers. They'll provide you with the best and most secure experience with QuickBooks. For more details, please see this article: System Requirements For QuickBooks.   

Furthermore, there are four different types of items: services, non-inventory, inventory, and bundles. These assist you in better tracking by categorizing the goods and services. You can choose wisely with the guidance of this article: Change product and service item types in QuickBooks Online.

If I can be of help while working in QuickBooks, feel free to let me know by adding a comment below. Have a wonderful day!