Could not able to see Custome labels

This is my alloy config but i could not see labels services_name
i can only see default labels filename

local.file_match “nginx_logs” {
path_targets = [{ path = “/var/log/nginx/access.log” }]
sync_period = “5s”
}

loki.source.file “nginx_log_scrape” {
targets = local.file_match.nginx_logs.targets
forward_to = [loki.process.nginx.receiver]
tail_from_end = false
}

loki.process “nginx” {
stage.labels {
values = {
services_name = “nginx”,
}
}

forward_to = [loki.write.default.receiver]
}

loki.write “default” {
endpoint {
url = “http://54.159.229.71:3100/loki/api/v1/push”
}
}

thank you it is working after using static_labels