activate
abstract fun activateDevice(activationCode: String, callback: TerminalCallback<DeviceActivationResult>): TerminalCall<DeviceActivationResult>
Activates this device with the six-digit code supplied by the integrator. DeviceActivationResult reports SUCCESSFUL or USER_ERROR with an error reason. A device already linked to a terminal rejects activation as INVALID_REQUEST, with non-retryable message Device is already activated. Use executeInitialisation to initialize the existing device. Activation never implicitly resets an already activated device. SoftPOS may await foreground enrollment startup within the request deadline; readiness or busy rejection is delivered through TerminalCallback.onFailure before the code reaches the backend.