P2419HC, VGA to HDMI not working

@NPatel412  Converting between VGA and HDMI requires an active signal converter chip that is built into the adapter.  Those converter chips are directional, meaning they're designed to either convert a VGA signal to HDMI (to connect a VGA output to an HDMI input), or an HDMI signal to VGA (to connect an HDMI output to a VGA input).  There both types of HDMI to VGA adapters on the market, so you might have the wrong one for the direction you're trying to go.  Or sometimes those active signal converter chips are problematic, because they're somewhat complicated, and complexity can introduce problems in the tech world even where problems shouldn't exist.

Another possibility is that the HDMI and VGA outputs on your system are sharing a common GPU output, in which case it wouldn't be possible to use both simultaneously.  Some Dell Latitude laptops work like this.

But if your system has a USB-C port that supports video output -- which is an optional capability of USB-C ports and not always implemented -- then you could use that instead, and you'd get better image quality because ancient VGA is an analog signal, whereas everything else is digital.  That's especially the case when trying to run 1080p, which is at the upper limit of what VGA can handle, so you're more likely to experience analog signal issues that will be especially noticeable on things like text.  In fact, if you have a video-capable USB-C output, since you have P2419HC displays you could even create a daisy chain to run BOTH of your displays from that single output.  You'd use a USB-C to DisplayPort cable to connect to Display #1, then use a DisplayPort cable to connect the DisplayPort output of Display #1 to the DisplayPort input of Display #2.  Don't mix up the outputs and inputs in this setup or it won't work.  But in this setup, your system will still see both displays independently, so you can still use them in Extend mode, but you'll only have one cable to deal with.