If you rotate it just right, (down 1, down 6, down 3, down 6, no move, down 3, no move, down 5, no move, and down 7) you get something like
PUZZLEYOUR PASSWORDIS THEMISSING CHARACTERS FROMALLTHE ALPHABETGO NOWANDTELL OURFRIENDS SPLENDIDLY TOOPENTHIS PUZZLEYOUR
showing up (one row repeated), which when cleaned up says YOUR PASSWORD IS THE MISSING CHARACTERS FROM ALL THE ALPHABET. GO NOW AND TELL OUR FRIENDS SPLENDIDLY TO OPEN THIS PUZZLE.
The missing letters (and thus the answer) are JKQVX.
And after all that, here's a picture from the OP of the vessel after you open it: