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Hi, I need help with the trophy merman on pc.
Teku swims from airbag to airbag for over a minute, but nothing happens.
Where is my mistake?

This is the discription to get the trophy:
"In the same cave where you unlock Nice try..., you will need to cross three steaming pillars to reach a shrine and some water on the other side. Lighting the shrine will turn off the steam and allow you access to the story progression in the water below.

Jump into the water and swim down into a large open chamber. In the top right corner and on the middle left side are two airbags you can use to refill your oxygen. Swap between the two, as once they've deflated, they cannot be used for a little while. Stay underwater for more than a minute and you'll unlock this trophy."

Is there a special moment to get it?
Before or after finding the pearl on the bottom?

Best regards, think13
You're probably not doing anything wrong. The trophy is probably just bugged, since, as far as I can tell, almost nobody has been able to get it with the GOG version of this game.
It's a version related bug. It happens with 1.1.17 but not with previous versions.