After a two-week break from making music, I got back to creating, but something happened. While adjusting the Scale settings and turning the Main Encoder, I noticed that the keyboard no longer responds to its commands. The model of the MIDI keyboard I’m using is the KeyLab Essential mk3 61. I would also like to clarify that the keyboard has never been subjected to any physical damage, and there are no visible physical defects on it.
I just solved the problem. For anyone facing a similar issue – just press down on the black panel under the Main Encoder. You’re welcome 
I have the same problem - what do you mean with “black panel”? under the main encoder is nothing only the keys
Hi @ElGrabolo
I would assume they might have the white version, which has a black panel around the main encoder and screen, it’s the same on the black version, just not as obvious, as seen in the pic below.
Although, yourself and the OP might want to still contact Arturia Support, as it sounds like there MIGHT be an issue with an internal connection.
HTH!