Unable to upload metrics to AI

I am trying to upload metrics using logstash-output-applicationinsights and it is failing. Below is the simple config and the output

#######################Logstash config example#####################
input {
#Test Data
#15,20,25,30,35,40
stdin { }
}
filter {
csv {
separator => ","
columns => ["cpu","mem","disk","network","swap","processes"]

}
}

output {
stdout { codec => rubydebug }
applicationinsights {
ikey => "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
ai_type => "metric"
ai_metrics_names => ["cpu","mem","disk","network","swap","processes"]
dev_mode => true
}

##########################Output##############################
{
"network" => "30",
"message" => "15,20,25,30,35,40\r",
"disk" => "25",
"processes" => "40",
"host" => "somecomputernamehere",
"cpu" => "15",
"mem" => "20",
"swap" => "35",
"@version" => "1",
"@timestamp" => 2019-12-13T17:17:33.993Z
}
[2019-12-13T11:17:34,294][ERROR][logstash.outputs.applicationinsights][main] Error occurred sending data to AI. {:exception=>#>}