Moshi. @Json annotation in parent abstract class is ignored

Question

I have an abstract class which has an annotated property

abstract class DataPoint(
    @Json(name="collected_at")
    @Iso8601Time
    val time: Long
)

@Retention(AnnotationRetention.RUNTIME)
@JsonQualifier
annotation class Iso8601Time

class Iso8601TimeAdapter {
    companion object {
        val TIME_FORMAT = SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS", Locale.US)
    }

    @Suppress("unused")
    @ToJson
    fun toJson(@Iso8601Time time: Long): String {
        return TIME_FORMAT.format(time)
    }

    @Suppress("unused")
    @FromJson
    @Iso8601Time
    fun fromJson(strTime: String): Long {
        return TIME_FORMAT.parse(strTime)?.time ?: 0
    }
}

Then I have an implementation of this class and a serialization code

class BpDataPoint(
    time: Long,
    val systolic: Int,
    val diastolic: Int)
    : DataPoint(time)

val bloodPressure = BpDataPoint(System.currentTimeMillis(), 112, 120)

val m = Moshi.Builder()
            .add(Iso8601TimeAdapter())
            .add(KotlinJsonAdapterFactory())
            .build()
val a = m.adapter(BpDataPoint::class.java)
val json = a.toJson(bloodPressure)

Althougth time property is marked with another name to serialize moshi ignores this annotation. Also custom adapter for the time field does not work as well.

This is the json I am getting

{
               "time":1620922108339, // I expect here "collected_at": "2021-05-13 19:25"
               "systolic":112,
               "diastolic":120
            }