Excel Macros disappear from xlsm file

One of my colleagues is also experiencing something similar to this. She's working out of a template spreadsheet that has macros tied to buttons to show/hide columns (for ease of use) and we've recently discovered that the macros tied to the buttons no longer exist. The modules where the macros should be living still do, but the macros themselves are gone. So, when the button is clicked, we get a VBA error and the spreadsheet basically locks up and doesn't allow it to be saved. Pretty frustrating but I get a little comfort knowing that others are having similar odd issues with macros at the moment. We're also running Office 365 with the latest Excel build, so I'm hoping it's just an issue with this particular build version.