getting error tech.allegro.schema.json2avro.converter.AvroConversionException: Failed to convert JSON to Avro Path in schema: --> payload__id

here is the avro schema -
{
"namespace" : "com.fetch.test",
"name" : "outer_record",
"type" : "record",
"fields" : [ {
"name" : "payload__id",
"type" : "string"
}, {
"name" : "payload_createdDate",
"type" : "long"
}, {
"name" : "payload_lastUpdate",
"type" : "long"
}, {
"name" : "payload_firstName",
"type" : "string"
}, {
"name" : "payload_lastName",
"type" : "string"
}, {
"name" : "payload_email",
"type" : "string"
}, {
"name" : "payload_birthDate",
"type" : "long"
}, {
"name" : "payload_phoneNumber",
"type" : "string"
}, {
"name" : "payload_last4DigitsOfPhoneNumber",
"type" : "string"
}, {
"name" : "payload_signUpPlatform",
"type" : "string"
}, {
"name" : "payload_bonusPointScheduleId",
"type" : "string"
}, {
"name" : "payload_allowedScopes",
"type" : {
"type" : "array",
"items" : "string"
}
}, {
"name" : "payload_role",
"type" : "string"
}, {
"name" : "payload_lifetimeSavingsFromCoupons",
"type" : "double"
}, {
"name" : "payload_deactivatedReason",
"type" : [ "null" ]
}, {
"name" : "payload_userTosAcceptance",
"type" : {
"type" : "array",
"items" : "string"
}
}, {
"name" : "payload_lastPointsViewed",
"type" : [ "null" ]
}, {
"name" : "payload_monthlyBudget",
"type" : [ "null" ]
}, {
"name" : "payload___deleted",
"type" : "boolean"
}, {
"name" : "payload___db",
"type" : "string"
}, {
"name" : "payload___rs",
"type" : "string"
}, {
"name" : "payload___collection",
"type" : "string"
}, {
"name" : "payload___op",
"type" : "string"
}, {
"name" : "payload___ts_ms",
"type" : "long"
}, {
"name" : "_id",
"type" : "string"
} ]
}

getting exception -- org.apache.kafka.streams.errors.StreamsException: Exception caught in process. taskId=0_5, processor=KSTREAM-SOURCE-0000000000, topic=mongoDev.Fetch_V2_Dev.Users, partition=5, offset=188, stacktrace=tech.allegro.schema.json2avro.converter.AvroConversionException: Failed to convert JSON to Avro
at tech.allegro.schema.json2avro.converter.JsonGenericRecordReader.read(JsonGenericRecordReader.java:53)
at tech.allegro.schema.json2avro.converter.JsonGenericRecordReader.read(JsonGenericRecordReader.java:41)
at tech.allegro.schema.json2avro.converter.JsonAvroConverter.convertToGenericDataRecord(JsonAvroConverter.java:66)
at topicFlatten.flattenJSON.parseJson(flattenJSON.java:32)
at topicFlatten.jsonTopicFlattenStream.lambda$flattenJSONStream$0(jsonTopicFlattenStream.java:62)
at org.apache.kafka.streams.kstream.internals.AbstractStream.lambda$withKey$1(AbstractStream.java:106)
at org.apache.kafka.streams.kstream.internals.KStreamMapValues$KStreamMapProcessor.process(KStreamMapValues.java:40)
at org.apache.kafka.streams.processor.internals.ProcessorAdapter.process(ProcessorAdapter.java:71)
at org.apache.kafka.streams.processor.internals.ProcessorNode.lambda$process$2(ProcessorNode.java:181)
at org.apache.kafka.streams.processor.internals.metrics.StreamsMetricsImpl.maybeMeasureLatency(StreamsMetricsImpl.java:884)
at org.apache.kafka.streams.processor.internals.ProcessorNode.process(ProcessorNode.java:181)
at org.apache.kafka.streams.processor.internals.ProcessorContextImpl.forwardInternal(ProcessorContextImpl.java:281)
at org.apache.kafka.streams.processor.internals.ProcessorContextImpl.forward(ProcessorContextImpl.java:260)
at org.apache.kafka.streams.processor.internals.ProcessorContextImpl.forward(ProcessorContextImpl.java:219)
at org.apache.kafka.streams.processor.internals.SourceNode.process(SourceNode.java:86)
at org.apache.kafka.streams.processor.internals.StreamTask.lambda$process$1(StreamTask.java:731)
at org.apache.kafka.streams.processor.internals.metrics.StreamsMetricsImpl.maybeMeasureLatency(StreamsMetricsImpl.java:879)
at org.apache.kafka.streams.processor.internals.StreamTask.process(StreamTask.java:731)
at org.apache.kafka.streams.processor.internals.TaskManager.process(TaskManager.java:1177)
at org.apache.kafka.streams.processor.internals.StreamThread.runOnce(StreamThread.java:753)
at org.apache.kafka.streams.processor.internals.StreamThread.runLoop(StreamThread.java:583)
at org.apache.kafka.streams.processor.internals.StreamThread.run(StreamThread.java:556)
Caused by: Path in schema: --> payload__id
at org.apache.avro.generic.GenericData.getDefaultValue(GenericData.java:1173)
at org.apache.avro.data.RecordBuilderBase.defaultValue(RecordBuilderBase.java:142)
at org.apache.avro.generic.GenericRecordBuilder.getWithDefault(GenericRecordBuilder.java:250)
at org.apache.avro.generic.GenericRecordBuilder.build(GenericRecordBuilder.java:227)
at org.apache.avro.generic.GenericRecordBuilder.build(GenericRecordBuilder.java:32)
at tech.allegro.schema.json2avro.converter.types.RecordConverter.convertValue(RecordConverter.java:37)
at tech.allegro.schema.json2avro.converter.types.RecordConverter.convertValue(RecordConverter.java:14)
at tech.allegro.schema.json2avro.converter.types.AvroTypeConverterWithStrictJavaTypeCheck.convert(AvroTypeConverterWithStrictJavaTypeCheck.java:22)
at tech.allegro.schema.json2avro.converter.CompositeJsonToAvroReader.read(CompositeJsonToAvroReader.java:92)
at tech.allegro.schema.json2avro.converter.JsonGenericRecordReader.read(JsonGenericRecordReader.java:49)
... 21 more