diff --git a/tools/node-rewards-scheduler/node_rewards_ingester.py b/tools/node-rewards-scheduler/node_rewards_ingester.py
index bed42f4..9e149dd 100644
--- a/tools/node-rewards-scheduler/node_rewards_ingester.py
+++ b/tools/node-rewards-scheduler/node_rewards_ingester.py
@@ -261,7 +261,7 @@ def _unwrap_optional(value):
 
     @staticmethod
     def _make_line(metric_name: str, value: int, ts: int, **kwargs) -> str:
-        return f"{metric_name}{{ {' '.join([f'{key}="{value}"' for key, value in kwargs.items()])} }} {value} {ts}"
+        return f"{metric_name}{{ {', '.join([f'{key}="{value}"' for key, value in kwargs.items()])} }} {value} {ts}"
 
     def wait_for_victoria_metrics(self):
         """Wait for VictoriaMetrics to be ready"""