I accidentally pressed a button and got this emergency landing alarm. But how do I land? The plane didn't descend automatically, or was it done manually? What's the procedure, please?

Emergency landing
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- Official Post
You pushed the EMER DES pushbutton on the pedestal. This arms the automatic emergency descent function. If you follow the steps on the right hand screen then the emergency descent will be initiated.
To disarm just press the EMER DES Button again.