Unable to connect the Bluetooth keyboard to the iPad

I connected my Bluetooth keyboard to my iPad Air 5. The connection was successful, but after 5 seconds it disconnects. I have tried everything, including resetting both the iPad and the keyboard, forgetting the device and reconnecting it in the Bluetooth settings. Previously, this keyboard always worked fine with my iPad. My device is an iPad Air 5 running iPadOS 18.6.2, and the keyboard is a Goojodog A1890.