Without the information requested in my previous response, I can only give you a general answer, but I hope this helps.
OK, let us see if we can get an error code or if it will reset.
Please try this and let me know if you get any error codes/flashing lights:
Press and hold Keylock and then Start/Pause for 5 seconds.
Now all LEDs except Keylock are illuminated, press Start / Pause, check if any light is flashing.
Then press Keylock and then press Keylock again to remove the previous fault.
Press Power to exit and try again, please let me know how it goes.
I hope this helps, please do not hesitate to ask any follow up questions.
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Have a wonderful evening.