diff --git a/index.js b/index.js
index 74d8944..a60cad2 100644
--- a/index.js
+++ b/index.js
@@ -511,7 +511,10 @@ exports.rate_conn_enforce = async function (next, connection) {
 
     let connections_in_ttl_period = 0
     for (const ts of Object.keys(tstamps)) {
-      if (parseInt(ts, 10) < periodStartTs) continue // older than ttl
+      if (parseInt(ts, 10) < periodStartTs) { // older than ttl
+        this.db.hDel(`rate_conn:${key}`, ts);
+        continue
+      }
       connections_in_ttl_period =
         connections_in_ttl_period + parseInt(tstamps[ts], 10)
     }