Configure Promtail on EC2 for EC2 tag

Hi Everyone, I have a question on promtail configuration on EC2 instance. My EC2 instance has a tag key as below

MY:APPZONE:Name .

I tried to add this tag value to promtail config file as below, but not success
- source_labels: [__meta_ec2_tag_MY:APPZONE:Name]

Any idea how to set the source lable?