There are several posts out there detailing this issue, for which Smartsheet has provided nothing in the way of a solution. Sharing a few for details:
I have submitted multiple cases on this myself.
"Merge saves" frequently revert many of the changes that I, as an admin, make to the structure of my sheets. This is a mockery of the supposedly collaborative nature of smartsheets. Often this happens when another user has the same sheet open for over a day and then decides to use it and save stuff based on a very outdated version, also deleting changes made by other users in the meantime. Ridiculous!
Hi, just signing in to add my vote. We urgently need a fix for this issue.
Agreed, though I have had an extremely hard time getting Smartsheet support to even recognize this as an issue. That is the part I find ridiculous.