diff --git a/check_matrix_synapse.py b/check_matrix_synapse.py
index 562ab6c..0fc5541 100755
--- a/check_matrix_synapse.py
+++ b/check_matrix_synapse.py
@@ -107,7 +107,7 @@ def main():
         db_lag_MAX = 0.01 if not args.crit else args.crit  # in seconds
         try:
             db_lag, null_present, raw_data = get_waiting_for_db(args.grafana_api_key, args.interval, args.range, args.grafana_server)
-            null_warn = f'Null data was present for this timeseries.\n{raw_data}' if null_present else ''
+            null_warn = f'Null data was present for this timeseries, value may be incorrect.\n{raw_data}' if null_present else ''
             if db_lag > db_lag_MAX:
                 print(f"CRITICAL: DB lag is {db_lag} sec. {null_warn} |'db-lag'={db_lag}s;;;")
                 sys.exit(nagios.CRITICAL)