Apple Wireless Keyboard, certain keys no longer working

First I thought this was a software issue, but I have since tried repairing my keyboard with a different OS on my current laptop, as well as an old one. Same results.

The left & right arrow keys, brackets, plus/equals sign, tilde sign no longer work.

I've replaced the batteries, reset the pairing by holding the power button while adding the bluetooth device.

I'm still left without those keys.

Any other suggestions?