Before you get to frantic----post a picture of the soffit and roof.
Then a picture of the attic insulation.
Attics need air flow to stay dry---air enters the soffits---travels across the bottom of the roof sheeting--then out through a ridge vent or mushroom vents--
Part of that system is not working (or is missing) in your home.
The most common one is a person adding insulation to the attic and plugging up the soffit vents.
More info needed.
Then a picture of the attic insulation.
Attics need air flow to stay dry---air enters the soffits---travels across the bottom of the roof sheeting--then out through a ridge vent or mushroom vents--
Part of that system is not working (or is missing) in your home.
The most common one is a person adding insulation to the attic and plugging up the soffit vents.
More info needed.