I experience with my Galaxy S9 where the install system update has been stuck in a loop for over a day. The phone would update to 25% and then reboot and repeat this loop endlessly. I tried pressing the volume down + power button at same time to stop the update. The phone reboots but returns to system update and repeat the loop again. I saw a similar topic "Galaxy s9 stuck in boot and update loop" in this community but didn't find a solution.
Please advise how to resolve this issue.