Hopefully you'll manage to get on soon!
I managed to log on ok (after spending an hour of playtime making one of my old pirates, lol) but had all sorts of issues including crashes and random disconnects. My cutlass disappeared for about 20 minutes, which was especially disturbing considering my attempts to replace it with a free Rusty Cutlass at a Smith kept timing out.
I changed oceans which seemed to help with stability a bit.
Except if you literally can't connect at all then maybe reinstall the launcher? If that fails might want to check that your virus checker isn't blocking access (had this issue with other games, not this one).