Why?. Wanhao duplicator 4s. IT disappear after restart. Can i uppdaterad software?
Looks like you have to update the Firmware
really common. Usually fixed by turning machine off and back on. To prevent get shielding for your lcd cables or ferrite filters for the existing cables
Most likely EM noise in the LCD ribbon cable, like @Jim_Squirrel mentioned.
That looks similar to an error I get on the marlin lcd all the time. Just pressing the encoder button to bring up the menu clears it up. I think it’s more an issue with no shielding on the wires but I’m probably wrong.
I get that a lot on my machines. Usually during a long print. It’s never messed up a print. Clicking into the menu normally resets the display.