Installed by snap. These command seems doing nothing.
I ran nextcloud.export -abc from my local computer where I had installed Contacts, Calendar, and did more thing and zipped the backups/dated folder
Then from my server, i downloaded and unzipped, them tried run nextcloud.import -abc that returned Maintenance on and off, then I went to Web UI it’s like starting afresh, no settings & apps showing that we’re from configured from local computer.