Wireless Keyboard will not enter pairing mode

I’ve had this black ultra-thin Bluetooth keyboard for a few years, and it’s worked great with an excellent battery life. I haven’t used it much, but I recently got a tablet that I wanted to use it with.

So I tried to pair it, and it wouldn’t show up on any of my Bluetooth devices (phone, laptop, tablet). I turn it on, the blue and green lights turn on, I press Fn+Z together, and nothing happens. I wait for the blue and green lights to turn off and press Fn+Z again, and nothing happens. No flashing light. Nothing shows up on my BT devices.

I read that perhaps the green light meant the battery was low, so I charged it to full last night. Tried again today, and the same thing is happening. Hoping that it’s a software issue on the keyboard itself, I’ve looked around for a reset pinhole, but can’t find one.

My next sequence of thought is to guess it’s a hardware issue. I have small children and this thing has been laying around for a while. My next step would be disassembly, hoping to find something that’s maybe popped out of place.

Suggestions on repair, or do you think it’s time for the recycle bin? Thank you in advance.