The routine clue there is that it tried 5 times (default –number-of-retries) for the same file, and never got it.
Though the log (unlike the --log-file log) doesn’t show seconds, the minutes imply the attempts took awhile.
The most interestingly suspicious to-the-second values are the 1 minute and 40 second (1:40) time reports because there looks to be a default timeout in the .NET Framework API that’s documented as 100 seconds.
Exactly how timeout is measured seems to be the subject of some debate such as this. The –http-operation-timeout documentation for Duplicati sides with this being the total allowed transfer time. With your oversized 500MB dblock files (–dblock-size default is 50MB, but there are certainly valid reasons one may set 500MB) the download might just be too slow, due to Microsoft, your connection, your computer, doesn’t really matter.
Could you try editing the job Options to add an Advanced option of --http-operation-timeout, select Minutes, and try 5 (to be generous)? The UI seems a little buggy, for example Custom on the dropdown doesn’t work.