OAuth2 authenticator problem

I saw the message from Gmail saying that using apps like fetchmail
would stop working on 30/05/2022. Searching showed that OAuth2
support was included in fetchmail-7.0.0-alpha so I installed it. Setting
up the oauth2 script was straightforward enough but I had a bit of a
tussle getting registered with Google! Eventually I could kick off
fetchmail and receive my mail. Thank you Matthew Ogilvie!

But (you knew this was coming :)) after about a day I started getting
fetchmail messages:

Mar 20 22:19:36 localhost fetchmail[29377] We've run out of allowed authenticators and cannot co
ntinue.
Mar 20 22:19:36 localhost fetchmail[29377] Authorisation failure on
[email protected]@pop.gmail.com (previously authorised)

I searched on this but couldn't find anything; I guess not a lot of
people are doing this. Have I left out some admin step? I have the
usual 10000 tokens per day available. I have a cron job refreshing my
access token.

Thanks
Robin
-- 
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Robin Atwood.

"Ship me somewheres east of Suez, where the best is like the worst,
 Where there ain't no Ten Commandments an' a man can raise a thirst"
         from "Mandalay" by Rudyard Kipling
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