https://imgur.com/sk0M6lX
We first tried fixing it by resetting the phone but all we see now is the welcome screen with the same lock icon. After conducting some research, I discovered that the lock indicates a remote device lock. This device was given to me by Google Store in replaced of another one that malfunctioned during its warranty period.
Now I'm waiting on Google Store to give a me . but so far it has being only a handful of back and forth emails with instructions to reset the device, that changes nothing, and questions if there is any liquid damage.
I'm very disappointed with their lack of effort to really solve the problem.