The latest firmware does not work. In addition to experiencing this firsthand, I have seen the same problem described on Reddit. The robot issues a "Finished cleaning" announcement and leaves huge areas untouched within the perimeter it has already cleaned. For example, it will clean half of a rug, then wander off never come back and finish with many areas uncleaned. If you have an S7, do not ever upgrade firmware for it. I have multiple S7 robots and the only one to do this has updated firmware. I have tried the factory reset procedure, but I never hear an announcement that it is restoring factory settings. Either I am doing this wrong or the feature has been taken away. I hope I am doing it wrong because I have a useless robot.
We are sorry to hear that your device did not work well.
The issue you faced may not be solved in a short answer. We hope we could work with you to locate the cause and address it. Would you please contact us at support@roborock.com(if you are in EU, contact support@roborock-eu.com)so that we can better assist?