Recover unsynced registers

Hi, i’m new here, i need help.

I developed an app and the automatic sync was off. So, when my partner used to insert data he had to sync all the time. Today, he inserted a lot of registers but instead of click the sync button he clicked the undo button. So, all the registers were not inserted. My question is, there is a way to recover them? Exist a cache or something like that? Where the non-inserted register are accumulated? These changes were lost forever?

I appreciate your responses, have a nice day

There is no way to recover.