I'm here to get the help you need when saving a customer in QuickBooks Online (QBO), cjsbuilders1972.
To be sure we're on the same page, I'd like to verify if you encounter some error messages when trying to save customers. It would help us fix the problem.
In the meantime, let's perform some troubleshooting steps by logging in via incognito mode or a private window. This way, it confirms if the cache is the cause.
Otherwise, switch to a different browser like Firefox, Google Chrome, or Safari. The one you are currently on may be having a temporary issue with QuickBooks, and using a new browser for the moment will allow you to get back to work.