If nothing so far has worked, you can clear the cache partition to see if corrupted data is keeping the phone from performing an update.
1. Turn off your phone by pressing the Power button on the side and tapping "Power off," then tapping "power off" a second time.
2. Press and hold the Volume Up and the Bixby keys, then press and hold the Power button. Hold all three buttons until you see the Android logo.
3. After the menu appears, use the Volume Down button to choose "Wipe cache partition" and then press the Power button to select it.
4. Use the Volume Down button to choose "Yes" and then select it with the Power button.
5. When the cache wipe is completed, press the Power button to select "Reboot system now."
After the phone restarts, try installing the update again. If it still does not work, you may want to contact Samsung technical support for additional help.
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