I might have useful information (EDIT: maybe not, see bottom) as to why this is happening. I have only had floccus for three weeks or so, but in the last week this has been happening to me as well.

Floccus is able to connect up to Nextcloud, but is unable to sync due to a "E017: Network error: Check your network connection and your account details | Last synchronized: 0 seconds ago". Expected ...

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