The Android security patch level for the original Galaxy Z Flip has been raised to June 2022 by a recent software update from Samsung.
The Galaxy Z Flip units with model number SM-F700F are receiving the update, which has firmware version F700FXXU8GVF3. It is now being seeded in Italy and will likely soon spread to other areas.
If you reside in Italy and your Galaxy Z Flip hasn't yet gotten the update, you may manually check for it by going to the Settings > Software update menu.