Bluetooth pairing code request not acknowledged

I am trying to connect a connect a Logitech slim combo to my Ipad (it's Ipad 6 but it meets my needs). The "Slim Combo" shows up under my Devices, but it will go further than that. It will not accept the code and then most times the "Slim Combo" disappears off the Device list after 1-2 minutes. I have tried this multiple times and same result. This older Logitech keyboard is charges by an "android" charger (so no coin batteries to replace - that I found). Both the Ipad and keyboard have been fully charged. I have tried turning off both and turning back on. I have tried pressing the bluetooth button on the keyboard. Nothing.

I've seen in flicker "Connected" but it stops in half a second. I have seen it seen it say "Connected" next to "Slim Combo" while a message is requesting me to enter the pairing code. Nothing seems to happen when I enter the pairing code and press enter.

So close yet so far away from using it! So frustrating.