Be sure to use the latest firmware for your printer type.
FLsun Q5
Download the firmware. Extract the Zip to the root of an SD card. Insert in to your unit and switch it on. The firmware will automatically install and takes just a few minutes. Do not power off until complete. There is also a video embedded in to this file to demonstrate.
V2.5
XYZ on 2208 drivers. E0 on 4988
1Mb Zip file
FLsun Q5 V2.5 firmware