When plugged it doesn't on what can be the cause

@tremainetrey you are not telling us what you have already checked.

Start off with the easy things. Disconnect the power from the computer by unplugging the power cord from your computer. Disconnect all external devices from the computer. Now hold the power button depressed for about 30sec-1min. Reapply the AC power adapter and see if your computer does show any sign of life.

If that did not work, you want to check your power supply. Make sure it has the proper voltage. Check to make sure that the connectors are not bend etc. Check the DC-in jack of your laptop. Make sure there is no corrosion, debris etc. that prevents it from working. Clean it of any debris etc, and use a few puffs of air to clean it out. If none of this works, get a ammeter and see if your laptop draws any amperage from the charger. After that, you need to check and see if your motherboard even gets power. For that of course, you need to open it up. Post Some good pictures of what you see. That way we can see what you see.

Use this HP Spectre Folio 13 Maintenance And Service Guide to work on your Folio and this Adding images to an existing question to show us what it all looks like.