2017 Macbook pro 13 inch 3 monitors help
The 13" 2017 MacBook Pro only supports up to two external monitors:


  Video Support
  
  Simultaneously supports full native resolution on the built-in display
  at millions of colors and:
  
  
  One display with 5120-by-2880 resolution at 60Hz at over a billion colors
  Up to two displays with 4096-by-2304 resolution at 60Hz at millions of colors
  Up to two displays with 3840-by-2160 resolution at 60Hz at over a billion colors
  


If you want to get a third display going, you will need a USB to DVI/HDMI/VGA adapter.