TP-Link Archer AXE75 AXE5400 Tri-Band Gigabit Wi-Fi 6E Router Black NOT WORKING

This is the Archer AXE5400 Tri-Band 6-Stream Wi-Fi 6E Router, Boxed with Ethernet Lead and Power Supply. Unfortunately, for the life of me, I cannot get it to power up. I can see nothing wrong with the unit, I've tested the power supply and that's fine. It just refuses to power up when switched on via rear button, which depresses just fine. No LED lights show on front panel. This is being sold as NOT WORKING, so no returns please. It maybe a simple fix, just not for me!

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