It looks like a hardware error.I'd start by opening the box up, and remove everything that can be removed (memory, harddisk, memory, cpu?, etc). Clean contacts and put them back. make sure everything is seated properly. Check for loose cables as well.Also there should be a 3 pin header there with a jumper on it, which determines the power-on behavior. In my box this is on the underside of the PCB, and you need to unscrew the cpu heatsink to get the board out, because the other side of the heatsink is glued to the casing. Check this jumper is present and either on position 1-2 or 2-3.If the system still doesn't boot, I'd send it back for RMA/warranty
It almost seems like it's trying to start up but gets a brownout and resets, which could indicate a bad power supply. It's not really flashing, but more like turning on and then losing power.Flashing or blinking usually has a fixed pattern which also happens when the PC is in standby mode.Anyhow, Qotom is pretty good at their customer service (for an Aliexpress supplier ) so I'm sure they'll figure it out and get you up and running.