you have to talk with minerva (she gives you the Goddess Dive), later go to valencia and search for a whirlpool (in the water) in front of the tavern
I got the goddess dive but the whirlpool still does not appear in front of the tavern.
did you do something special, where exactly did you find the whirlpool?
thank you, but it appears that my save is glitched or something like that.