Sony XPeria irresponsive during (after?) upgrde

I got a message a few days ago that there was a Sailfish OS update for my Sony Xperia 10 III.
This morning I made a backup, connected to WiFi and power and started the update. After a while I looked and had to provide the password and then once more and the Sailfish Logo shows and the white progress bar started filling.

It has now been more than 2 hours that the bar was complete and the phone is unresponsive to pressing any of the buttons on the side (tried for up to 15 seconds).

I don’t think waiting longer is going to help. Is there a way to reset/restart the phone? If so, how?

Time to reboot, see here:

I found that the phone reacted to pressing the volume and on/off button at the same time.

After that it switch off, and I could switch it on in the normal way. And the system tells me it is updated.