Mac OS High Sierra with Dual Monitors in Closed Clamshell

I have a 2015 Macbook Pro Retina and I used to run two dual 1080p 27" Acer monitors with my Macbook Pro in closed clamshell on Mac OS Sierra without any problems. However, I just updated to Mac OS High Sierra today and for some reason I can only get one of my monitors to work as an additional display for my mac. I have one of the monitors connected directly to HDMI and the other connected to Thunderbolt through an HDMI to Thunderbolt adapter. I've tested that both displays can act as an additional display to my mac but they will not both work at the same time (whether I'm in closed clamshell mode or not). I made sure that my mac is connected to power and have tried the steps in article HT201834. I would appreciate it if anyone has any additional tips or has ever encountered this same issue, thank you.