There seems to be some good news for the Samsung Galaxy S6 SM-G920F users as they can now get their handsets updated to Android 5.1.1 Lollipop firmware that is available from G920FXXU2BOFL build number. To get the firmware update that allows to fix issues related to bugs and improve user experience, you will just have to follow some simple steps:
Update and improve
Start with downloading Android 5.1.1 Lollipop update for your model and get the zip file 
extracted. Once done, download and extract Odin. Run Odin3 v3.10.6.exe on the device as an Administrator. Then switch off the phone, boot it again in the Download Mode by holding and pressing the Volume Down button along with the Power as well as Home buttons. Once the warning sign appears on screen, press Volume Up button.
Get Galaxy S6 connected to PC using an USB cable. You will get a message in Odin as “Added!!” and the first box that you will find just under ID:COM has a blue background. Now get the firmware added to Odin by disabling the “Re-Partition” option and enabling the “F.Reset Time”and “Auto Reboot” option. Now, press Odin’s start button for enabling firmware flashing. Once the firmware is installed, phone will reboot and users will be provided with a PASS message. Yet, before starting the update, get backup and ensure full charging of the device. Also install Samsung Galaxy S6 USB drivers.
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