Messages not loading into SilverTable from Topic

Question

Trying to load messages from Topic into a silverTable in the WriteStream. But the messages are not loading into silverTable. How to read the messages into silverTable?

var df = spark
  .readStream
  .format("kafka")
  .option("kafka.bootstrap.servers", "10.19.9.4:1111")
  .option("subscribe", "testTopic")
  .load()
df = df.select($"value",$"topic")

// select the avro encoded value and the topic name from the topic
df.writeStream
  .foreachBatch( (batchDF: DataFrame, batchId: Long)=>
    {
      batchDF.persist()
      val topics = batchDF.select("topic").distinct().collect().map(
         (row)=>row.getString(0))
      topics.foreach((topix)=>{
        val silverTable = mappings(topix)
        // filter out message for the current topic
        var writeDF = batchDF.where(s"topic = '${topix}'")
        //  decode the avro records to a spark struct
        val schemaReg = schemaRegistryMappings(topix)
        writeDF = writeDF.withColumn("avroconverted",
           from_avro($"value", topix+"-value", schemaReg))
        // append to the sliver table
        writeDF.write.format("delta").mode("append").saveAsTable("silverTable")
      })
    }