My calculator turns on but unresponsive to the keyboard.

"Augustine has a good suggestion, try removing the AAA batteries and the backup battery, then try replacing them. If any of them are corroded, they may have permanently damaged the buttons.

If that doesn’t help, here’s a guide on getting to the keys that may help. Once you’ve gotten to the main board, check for any loose or dirty connections.

If you find the buttons are beyond repair, you can buy a cheap, used calculator and swap out the motherboard."