Safe room temperature for sleep room is it 15-19 degrees

Red Nose does not suggest a specific room temperature for babies sleep, however, recommends dressing baby according to room temperature, using light weight clothing/bedding that can be added &/or removed as necessary.
https://rednose.org.au/article/how-to-dress-baby-for-sleep
https://rednose.org.au/article/what-is-a-safe-room-temperature-for-sleeping-baby
https://rednose.org.au/article/protecting-baby-from-overheating-during-sleep