Advanced Sleep monitoring can not be activated on my S62 !!!!

My S62 is showing all details of my sleep (movement, phases) but no pulse oximeter!!

When is follow the instruction it says I should "To enable pulse oximetry or to adjust the pulse oximeter settings, select 'Device Settings' > 'Fitness Tracker' > 'Pulse Oximeter'."

But I only can switch Fitness Tracker - on /off but no Puls Oximeter!!

How can enable that feature???