God of War Ragnarök

Hafguf is a huge jellyfish and you need to free two of them.
Both in the elven world of Alfheim.
The first jellyfish you will find after visiting Alfheim with Tyr, when Atreus hears the animal's moan.
At the end of the mission, when Tyr escapes into the portal, the elves make our way into the desert, where we can find the first jellyfish.
The second jellyfish is located in the distant desert, which is sealed with a rune.
You can get there by requesting "Sanctuary of the Elves", which is given by the elves in Freyr's camp in Vanaheim.
They ask you to bring knowledge from the old library - this will lead us to the second part of the desert and at that time you will already be able to open sealed magic runes.
Already in the distant desert, the quest to free the second jellyfish is activated and you will need to find a way down.

I had this bug: when you free the first jellyfish, be sure to save BEFORE throwing the axe to remove the roots. I had a graphical bug, the roots in the cave did not disappear. So I could not free the jellyfish from above the desert. It remained closed for me.