Replaced my LCD/Screen. Everything went smoothly, but now the display

Hello there! I just replaced the screen/digitizer/LCD on my iPad 4th gen iPad air. When I got the new panel on, the screen lit up as expected and I was able to test the device for about 30 seconds, before it went dark again. Now, when I press the power button, the device flashes on for a split second then off again. I suspected the display I bought was bad, so I put the cracked one back on, and the same thing occurs. I am not sure how to proceed at this point. Again, the iPad IS booting properly. I can briefly see the lock screen. It’s brief enough to where I can see the lock screen and read the battery level of 70%. Do you have any tips or ideas?