It seems that I have the same problem with you. And after checking my sql page(https://dash.infinityfree.com/accounts/if0_37997384/databases), it seems that the sql is offline because it is also not able to creat new database.
“Connection refused” implies that the database is only down, not missing. There are some signs suggesting that one of the database servers had an outage earlier, but it should be back up now. Your website also seems to work as far as I can tell.
If the database server is down, the panel cannot get the list of databases from the database server, which is why it will say there are no databases if the database server is down. They should appear again as soon as the database server is back up.