Just installed my first hackintosh.

Hi, i just installed my first hackintosh. I cannot use my second monitor. I have 1 monitor connected in gpu and another in motherboard. monitor connected in gpu is working. but the one connected in mother board is not connecting. My hackintosh is using opencore. i have installed with this guide. https://www.youtube.com/watch?v=GGy3V3YT6tI. Thanks

My build:

i5 6500 processor

16 gb ram

AMD rx 560 gpu