XPS 15 7590, WD19TB, Dual U2414H resolution issue

Hi,

I have an XPS 15 7590,  WD19TB thunderbolt dock, and dual (out of warranty) U2414H both connected via DisplayPort. The U2414H were working fine and suddenly it stopped working. I think it might have stopped working after I disconnected the thunderbolt port while the laptop was on standby not sure though. No idea if it's driver, dock HW or Laptop issue. I had this same issue before and after reinstalling Intel UHD and Nvidia drivers it started working again but this time can't make it work. One of the monitors doesn't show in the device manager, second shows as Digital Flat panel 640x480.

After doing some further research, I figured out that the issue is not the dock or the XPS laptop but it's the monitors. It turns out that U2414H have manufacture DisplayPort issue. I've managed to make them work again, apparently if you disconnect the power cord while DP input is selected it sometimes fixes the issue. Unfortunately, because I had always used the HDMI and had never used the monitors DisplayPorts until recently when I bought my new XPS laptop and dell dock I didn't know the about DP issue.

U2414H (warranty expired on November 20, 2018)
U2414H (warranty expired on January 20, 2018)