To close all your shutters at the same time and without voice assistants, you can:
Create a scenario.
It could not be easier:
(clicking in the middle at the bottom)
Then in define a condition, click on "Type to execute"
Then click on "run device"
Then Choose your Vollo or Vollo MAX
Choose ► switch
Specify whether you want to ► open or ► close
again add a task by clicking on the "+" which is in front of the word "Task"
Repeat the same operation with your other Switch
You will get this:
The next time to open all your shutters, all you have to do is activate the scenario you have created.