Macbook Pro (circa 2018) won't turn on

I was re-installing the macOS to my perfectly functioning Macbook Pro (due to an ownership change) recently and set it down elsewhere and was not monitoring the install that was in progress. Several hours later, I went to check on it and the screen was black and nothing seemed to be going on. I hit the power button and nothing happened, and now I am stuck in this state - it won't power on at all. I have tried using an external drive to boot up the OS, but there is absolutely no response from the laptop - it is not that it is running and I have the black screen, it is that there is absolutely nothing happening when I try to power it on. This laptop was functioning perfectly until I attempted to reinstall the OS, and I'm not sure what is going on now. Any suggestions would be greatly appreciated!!