If your device has a firmware version of 1.x.x the update cannot be carried out!
In the event of large version jumps, incremental updates are first necessary. These updates are available here:
If your device has a previous firmware version of at least 2.0.0 but before 2.2.0, an intermediate update step to 2.2.1, and then an intermediate update step to 2.6.2 must be performed before.
If your device has a previous firmware version of at least 2.2.0 but before 2.6.0, an intermediate update step to 2.6.2 must be performed before.