Why dont my ubs to vga adapters work from amazon?

I have the usb 3.0 7 port hub and i have 6 monitors( all vga connections). to connect them im using the display link usb to vga adapters 2.0 and there all connected to the hub and then connected to my pc that way. I ordered all my devices through amazon except the hub it was directly ordered through plugable. The adapters worked for a couple of days and one morning when i turned everything on the green light on the adapters turned off and only my main monitor thats directly connected vga to my pc stayed on. Idk what the heck is going on I’m not super techy but I’m not green to trouble shooting basic problems and I just cant figure this out