Here is the full list of all 39 The Telephone achievements.
The mystery begins.
You received your first call.
You haven't used the phone in time.
You scared away the crow.
Begin your visit to the abandoned town.
You found the lighter.
You paid tribute to the deceased girls.
You found the key to the second district.
You met Giulia.
You found a hidden jumpscare.
You met Chiara.
You met Father Sebastian.
You solved the chalkboard puzzle.
You obtained the blessed cross.
You solved Arturo Colombo's puzzle.
You fixed Lonely Plain's water system.
You gave water to the black bull.
You found the blessed axe.
You talked to Giulia and Father Sebastian.
You obtained the classroom key.
You cleaned the school sinks.
You solved the Tic Tac Toe puzzle.
You solved the mirror puzzle.
You solved the hat puzzle.
You finished The Telephone.
You found all the Lonely Plain Trading Cards.