diff --git a/src/panels/lovelace/cards/hui-history-graph-card.ts b/src/panels/lovelace/cards/hui-history-graph-card.ts
index a9b4d52a1b..50e4e59ce0 100644
--- a/src/panels/lovelace/cards/hui-history-graph-card.ts
+++ b/src/panels/lovelace/cards/hui-history-graph-card.ts
@@ -135,6 +135,10 @@ export class HuiHistoryGraphCard extends LitElement implements LovelaceCard {
     const { numeric_device_classes: sensorNumericDeviceClasses } =
       await getSensorNumericDeviceClasses(this.hass!);
 
+    if (!this.isConnected) {
+      return; // Skip subscribe if we already disconnected while awaiting
+    }
+
     this._subscribed = subscribeHistoryStatesTimeWindow(
       this.hass!,
       (combinedHistory) => {
@@ -212,7 +216,9 @@ export class HuiHistoryGraphCard extends LitElement implements LovelaceCard {
   private _setRedrawTimer() {
     // redraw the graph every minute to update the time axis
     clearInterval(this._interval);
-    this._interval = window.setInterval(() => this._redrawGraph(), 1000 * 60);
+    if (this.isConnected) {
+      this._interval = window.setInterval(() => this._redrawGraph(), 1000 * 60);
+    }
   }
 
   private _unsubscribeHistory() {