[Help me] Way for screen orientation change from portrait to landscape.

[szasurada]

I have purchased PocketLCD product in web shopping site.
And i have SBC(=single board computer) Khadas VIM3 Pro, under the basic setting status, Android 9 pie version.

Of course, when i connect PocketLCD to my windows pc, PocketLCD outputs normal screen.
However, when i connect PocketLCD to my Khadas VIM3 Pro, PocketLCD outputs abnormal screen. (T_T)
(About this issue, i had asked help to Khadas community bulletin, in my idea, it seems that vertical display support from Khadas takes so many times... (T_T))

So, I hope to ask your favor if it is possible.
Do you know the way for screen orientation change from portrait to landscape on PocketLCD?
If you have the solution, Please help me. (^^)

Thanks for your attention on my message.
Thank you! (^^)