Sometimes I cannot connect anymore to my Mi Band 3 with Bluetooth.
If I then turn off Bluetooth on the S10, I cannot switch it on anymore. I have to reboot the phone to get Bluetooth back.
I've noticed the Fitbit app regularly complains about last sync. I open the app and its reconnecting to my Fitbit band.
I assumed it was an Android 10 /Fitbit app compatibility thing that Fitbit would have to update.
Maybe I'll send Samsung feedback in case it is a bluetooth issue.