Recently, when I edit a new transaction (eg. change default title and, particularly, add notes on the box), the notes I add on the box do not get saved when I come out of the transaction. That's to say, I add notes on the box, I save the transaction, I click on the transaction again to check, and the text I added on the box has disappeared. This has happened a few times now, so I don't rely on this save action anymore. What I do now is: I add the details I need on the box, I do a Ctrl + C of the text, I save the transaction, I come out of it, I go back to it to check, and, as feared, the text is not there, so I do a Ctrl + P to paste the details back into the box, then I save it, I come out again, I go back to check and, then, this time the text has been successfully saved.
Can you try some troubleshooting and see if that resolves the issue you have been having.
Can you clear your cache and cookies, this link here will help you, can you close the browser down, reload it and log into your account and see if it lets you save the information and or if not let us know if you still have the same issue.