Did you follow all instruction from this page before updating firmware :
https://support.ledger.com/hc/en-us/articles/360002731113There is also info :
Please be patient
As many users are updating their device, it may take a few minutes to connect to our HSM server
For error you get only way around is to boot in Recovery mode and then open Manager -> click on update. To update to last firmware you need firmware version 1.4.2 and Ledger Live version 1.3.
Well I did a mistake this time, didn't delete the app before.