Multiport adapter (ModelA2119) blocks display to external monitors

Hi! I have the USB-C to Digital AV multiport adapter (ModelA2119). My goal is to connect TWO older external monitors that have HDMI ports to my Macbook Pro which only has two USB-C ports. One of those ports will be my charging cable, so there's only one port left to communicate to these two monitors. I bought a cable from Amazon (HDMI to USB-C) cable. When I plug in this cable directly from one of the monitors to my MacBook Pro (Model A2159) it works and I can see my display on the external monitor. But when I introduce the multiport adapter it doesn't work. There's no display, the laptop doesn't seem to recognize the external monitor. I've tried restarting and sleeping the laptop. I've tried plugging in the HDMI to USB-C cable before and after plugging the multi adapter into the laptop. I've tried the "detect displays" button in system preferences. Nothing. Can someone please help! Thanks!