when i add project to an existing customer the save button isn't highlighted for me to save it.

You are on the right track with adding the project, Jason. I'll provide details to help you address the error encountered in QuickBooks Online (QBO).

Before proceeding, verify that all necessary details have been entered before saving. If all details are in place, the issue might be related to your browser.

Firstly, try logging into your account using a private or incognito window to add a project to an existing customer. Ensure you add Intuit as a trusted site and use the latest versions of browsers supported by QuickBooks Online. Here are instructions to open a private window in your web browser:

• Google Chrome, press CTRL  + Shift + N
• Mozilla Firefox: press CTRL  + Shift + P
• Internet Explorer: Press CTRL  + Shift + P
• Safari: press Command + Shift + N

Using these up-to-date, supported browsers can often resolve unexpected behavior in QBO.

I'm also linking this article to help you learn how to use reports to track your project profitability and progress, including information on the latest financial reports for projects.

Feel free to return here if you have any concerns regarding adding projects or other customer-related transactions. We are here to provide prompt and thorough assistance.