Can't access underwater farm

[Maddorable]

I got to Town rank A a long time ago and had finished all the merfolk storyline. Unfortunately, I don't know how to access my underwater farm. I can see the place on the underwater map but the access is locked (I see only plants where the entrance is supposed to be according to the map). How can I start farming? I've been playing five days with the new 1.1 update but no letter, cutscene etc. to trigger the event.

[Tranquillian]

EDIT:
Played one more day and got the letter and quest. One thing I did the previous day was go to the laboratory and triggered a cut-scene about "Song of the sea". Not sure if that did anything. Played about 6-7 days after the patch before I got the quest.

Pre-edit:
I have the same problem. I did trigger a new Merfolk storyline when a new season started, called Starlet Expedition (bring Princess to dry land). I don't think this is the farm quest-line though. Currently working on getting Town rank S to see if that triggers it. I am able to access the vendor for the barn and animals but can't place barn because the area is not cleared.

[Maddorable]

All right, I received the letter for this quest after 6 days. 😂