Hello there, user05899.
Sometimes, error messages can be caused by a browser-related issue. We can do troubleshooting to get this sorted out.
Let's start by opening your account using the private browser or incognito mode.
Here are the keyboard shortcuts:
- Google Chrome: press Ctrl + Shift + N
- Mozilla Firefox: press Ctrl + Shift + P
- Internet Explorer: press Ctrl + Shift + P
- Safari: press Command + Shift + N
Then, try to create and save the new invoice. If it works, the final step is to clear the cache on your regular browser. Alternatively, try using a different browser.
Please let us know if you have any additional questions. Thanks.
