The external monitor shows OUT OF RANGE when closing the MacBook pro's screen.
It worked well when I close the Macbook2018's screen, just using the external BenQ EW3270ZL screen. But it shows OUT OF RANGE after configuring the display preference as Scaled 1080i( I forgot the specific figures) when I used the only external monitor. When I open the MacBook's screen, the two screens can work well, but closing the MacBook's screen show the error info.
I got some info about the reasons that caused this problem, but I don't know how to reset this configuration. Do I need to reset the E-GPU or the Monitor? and where can I find this answer?
Could you guys give me any instructions? Many thanks.