Sometimes the latest firmware causes more problems than it solves. If you need an older version (e.g., Tizen 3.0 or 2.3.2), you cannot downgrade due to Samsung’s rollback protection (eFuse). However, if you are moving from a different region to an older build of the same bootloader version, it may work.
Check XDA Developers’ Gear S2 forum. Members archive older builds. Again, verify the file hash before flashing. Samsung Gear S2 Sm-r720 Firmware Download
Note: Do not proceed unless you are comfortable with risk. Sometimes the latest firmware causes more problems than
Before attempting to download any firmware, you must understand the unique history of the Samsung Gear S2. Unlike most smartwatches, the SM-R720 exists in two distinct software states, and crossing them incorrectly can "brick" your device. Tizen 3.0 or 2.3.2)