Hey MauroF,
To give some clarification on this, the configuration of your device is stored on the dashboard. Hence when you remove your MX from your dashboard network, the configuration is retained on the dashboard itself. If you add the MX back to the same network or add another MX into the same network, the stored configuration will be applied to that device.
When moving devices across organisations, it is important to note that the configuration is NOT transferrable. However, you may temporarily experience some old configuration on the moved device.
For example, if you have your MX in a Network A in Org A, and you remove it from Network A and unclaim it from Org A, then claim it into Org B and add it to Network B, the device should pick up the configuration of Network B. Yet, in some circumstances the device may locally retain the old configuration settings from Network A, hence a hard reset (holding the physical reset button for 30 seconds) should resolve this.
If at any point you wish to move the device back to Network A in Org A, you can do so at any point and once done the device should pick up the configuration of Network A. Again, in some circumstances the device may locally retain the old configuration settings from Network B, hence a hard reset (holding the physical reset button for 30 seconds) should resolve this.
Hope that helps!
If you found this post helpful, please give it Kudos. If my answer solved your problem click Accept as Solution so others can benefit from it.