Nest integration: failing at last stage

Hello,

after upgrading to the last HA version:

|Versione|core-2022.6.1|
|Tipo di installazione|Home Assistant Container|
|Sviluppo|false|
|Supervisor|false|
|Docker|true|

I tried to set up the Nest integration following the new instructions in Nest Integration.
I think everything was fine, since I had no issue up to the very last stages: in the “Device Setup” chapter, I followed all the “OAuth and Device Authorization steps”, finding my own device, granting required permissions, Iinking the account…

Then the screen brings me back to Home Assistant, I have a panel saying something like “Loading the next step for Nest” which changes, after several minutes, to “Error”.

In the HA log I have the following error, not really explicit (at least for me):

Logger: aiohttp.server
Source: /usr/local/lib/python3.9/site-packages/aiohttp/web_protocol.py:405
First occurred: 10:03:20 (1 occurrences)
Last logged: 10:03:20

Error handling request

Looking on Google I found this site which says that “405” correspond to HTTPMethodNotAllowed. I do not know why and if this information is pertinent…

I tried several times, always with the same results…what’s going wrong?
Thanks in advance for help