On my S21- 5 Ultra sometimes when I go and push the On-Off switch to turn it on it will go on for a half a second then go off. It might do this 3 or 4 times before staying on.
Anyone else have this problem?
Yeah. Go ahead and do the volume up and power button until samsung logo appears, release the power button and recovery mode screen should appear. Use volume down key to go to wipe cache partition, then power key to select, then select "yes" with the side keys again, after, use side keys to go down to "repair apps" and select with power key. Phone should boot up after re optimizing apps. This will not delete any personal data