Planned update to v19: task was successful, but firmware is still old. One alert in firewall that a firmware update is started


I wanted to schedule the update to v19 yesterday for 23:50 and I set that too. Today I see in the portal that the task is registered as successfully run, but the firmware on the firewalls (2x 2 in HA) is not yet up to date. I have an alarm on each of the firewalls that a firmware update has been started.
Why does this not work? Manually on the firewall I can not load a v19, supposedly the v18.5.3 is the latest.
At home on my vm installation I could already install the update.