iMac M1 magic keyboard problem. Some keys presenting random function...

Hi,

We have this iMac M1 at home and it's wireless magic keyboard suddenly stopped working.

We didn't take it to repair as the problem appeared after one year of purchase, so, it's not at warranty anymore...

We plugged an old iMac wired keyboard (using an USB-C to USB adapter) and that's how we're using it with the benefit of two USB ports on the keyboard useful for connecting old usb devices like pendrives etc.

Some days ago I decided to give the magic keyboard a try and it connected and worked again but the delete and down arrow keys are presenting a erratic behaviour. Every press changes it's function. Sometimes it types the A character, another press, Q character, another press, volume up, brightness up and so on. It random its function at every press.

I was wondering if it's a firmware problem and if it's possible to bring the magic keyboard to life again.

I have more apple wireless keyboards, from 2003 and 2007, both working like new and this iMac M1 one lasted only more than a year...Hoping it's not a hardware problem for such recent buy.

Any help would be appreciated!