Running the documentation will initialize the VCS folder (where Pulse store thes changes). If the VCS folder is not initialized the Change Tracking will not work.
If the Change Tracking does not work or stopped working, you should check the TM1 credentials in the Pulse instance settings.
Adding to Vincent’s comment, It is important to configure Instance settings properly, as the Version Control System of Pulse is the backbone of Migration, because is with the data store in the internal git repositories of Pulse where migration performs comparisons and decides if creates or updates an object.
Regards,
Erik