AndroidRuntime error: Parcel: unable to marshal value
Your HashMap itself is serializable but is the Bottle class serializable? If not, it will not serialize and will throw errors at runtime.
Make the Bottle class implement the java.io.Serializable interface
I was getting this error because my class wasnt Serializable. To make my class serializable I had to add : Serializable at the end of class to make is Serializable. Just like this
class Shirt(val price: Double, val discountedPrice: Double) : Serializable
Make sure to import Serializable like this
import java.io.Serializable