The circuit shown above should work without issues, and flash the LED every few seconds. There is not really much to go wrong in these circuits if you keep the divider resistance down relative to the timing resistor (which you have done). I've used many thousands of the better spec'd 2N6028 in decades past.

Perhaps the 2N6027 is damaged, is actually something else, or perhaps the wiring is wrong. Some datasheets show the TO-92 pinout from below which can cause confusion. This one is clear.

The circuit shown above should work without issues, and flash the LED every few seconds. There is not really much to go wrong in these circuits if you keep the divider resistance down relative to the timing resistor (which you have done). I've used many thousands of the better spec'd 2N6028 in decades past.

Perhaps the 2N6027 is damaged, is actually something else, or perhaps the wiring is wrong. Some datasheets show the TO-92 pinout from below which can cause confusion. This one is clear.

So I suggest you check the pinout and if it appears okay and you've tried another part from the same batch, get another part from a trusted source such as Mouser, Digikey, LCSC etc.