Dashboard arguments

While following the tutorial to understand the Artiq dashboard I came up with the following situation:
`from artiq.experiment import *

class ScanExperiment(EnvExperiment):
"""AO tutorial"""
def build(self):
self.setattr_device("core")
self.setattr_device("fastino0")

  
    self.setattr_argument("voltage_0", NumberValue(default=0.0, unit="V", min=0, max=10))
    self.setattr_argument("voltage_1", NumberValue(default=0.0, unit="V", min=0, max=10))

def run(self):
    self.init()

@kernel
def init(self):
    self.core.reset()
    self.core.break_realtime()

    self.fastino0.init()
    self.fastino0.set_group(0, [self.voltage_0, self.voltage_1])
    
    self.core.break_realtime()

`
In principle this should allow me to change the voltage output of two channels, but nothing happens when I run the code via dashboard. There is also no error message.
Also I tried to make it an interactive argument and also get no message about what is happening.
What could the problem be?