Did you install the 13.0.3 or 13.1.1 update?
(you're probably on 13.0.2 or 13.1.0)
In Bridge click edit/camera raw and uncheck the option to open TIFF in ACR. Bridge has a habit of recaching layered TIFF's so the file is unavailable. Known problem, awaiting a fix.
I did that but still experiencing the problem. If I wait too long to save a layered file ( hour or so ) that is when it seems to happen. Otherwise most other times I am able to save out a layered photoshop file. Other coworkers are experiencing it as well even after the update. Saving to desktop sometimes works, but it is hit or miss with different ways to save it out ( desktop, different name, large format file, layered tiff, click close on the file then it asks you if you want to save and I say yes and it saves...) If all options fail we are forced to just flatten and save a tiff and loose our layers.