#FAIL message when rooting LG G Vista

I've tried a script and I've tried a program. Both give the same result. On Android 5.1 by the way.

It's not because it couldn't find the serial port, by the way. It only said that this time around because I switched it from MTP to PTP like someone said to do.

Full log:

Code:

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Starting adb server...
* daemon not running. starting it now on port 5037 *
* daemon started successfully *
Waiting for device...
Device detected!
Pushing files...
3486 KB/s (1048328 bytes in 0.293s)
1792 KB/s (9226 bytes in 0.005s)
3958 KB/s (4017098 bytes in 0.991s)
Rebooting...
Looking for LG serial port...
Serial port not found! please insert the phone manually into Download mode.
Disconnect the USB cable and turn off the phone.
Then press and hold the Volume Up button, and while you're doing that connect the USB cable again.
Waiting for device...
Phone found at COM3!
Rooting phone...
Author : blog.lvu.kr
SPECIAL COMMAND : ENTER, LEAVE
#FAIL
#
Done!

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