diff --git a/server/src/controllers/analytics_controller.ts b/server/src/controllers/analytics_controller.ts
index a1f5b76..50380c2 100644
--- a/server/src/controllers/analytics_controller.ts
+++ b/server/src/controllers/analytics_controller.ts
@@ -277,6 +277,16 @@ export async function runLearning(id: AnalyticUnit.AnalyticUnitId, from?: number
 
 export async function runDetect(id: AnalyticUnit.AnalyticUnitId, from?: number, to?: number) {
   let previousLastDetectionTime: number = undefined;
+  let range: TimeRange;
+  let intersection = 0;
+
+  let oldCache = await AnalyticUnitCache.findById(id);
+  if(oldCache !== null) {
+    intersection = oldCache.getIntersection();
+    oldCache = oldCache.data;
+  } else {
+    await AnalyticUnitCache.create(id);
+  }
 
   try {
     let unit = await AnalyticUnit.findById(id);
@@ -284,7 +294,6 @@ export async function runDetect(id: AnalyticUnit.AnalyticUnitId, from?: number,
     let analyticUnitType = unit.type;
     const detector = unit.detectorType;
 
-    let range: TimeRange;
     if(from !== undefined && to !== undefined) {
       range = { from, to };
     } else {
@@ -292,12 +301,6 @@ export async function runDetect(id: AnalyticUnit.AnalyticUnitId, from?: number,
     }
     const data = await query(unit, range);
 
-    let oldCache = await AnalyticUnitCache.findById(id);
-    if(oldCache !== null) {
-      oldCache = oldCache.data;
-    } else {
-      await AnalyticUnitCache.create(id);
-    }
     let task = new AnalyticsTask(
       id,
       AnalyticsTaskType.DETECT,
@@ -309,23 +312,11 @@ export async function runDetect(id: AnalyticUnit.AnalyticUnitId, from?: number,
     const result = await runTask(task);
 
     if(result.status === AnalyticUnit.AnalyticUnitStatus.FAILED) {
-      await Detection.insertSpan(
-        new Detection.DetectionSpan(id, range.from, range.to, Detection.DetectionStatus.FAILED)
-      );
       throw new Error(result.error);
     }
 
     const payload = await processDetectionResult(id, result.payload);
     const cache = AnalyticUnitCache.AnalyticUnitCache.fromObject({ _id: id, data: payload.cache });
-    const intersection = cache.getIntersection();
-    await Detection.insertSpan(
-      new Detection.DetectionSpan(
-        id,
-        range.from + intersection,
-        range.to - intersection,
-        Detection.DetectionStatus.READY
-      )
-    );
 
     // TODO: uncomment it
     // It clears segments when redetecting on another timerange
@@ -336,12 +327,29 @@ export async function runDetect(id: AnalyticUnit.AnalyticUnitId, from?: number,
       AnalyticUnit.setDetectionTime(id, payload.lastDetectionTime),
     ]);
     await AnalyticUnit.setStatus(id, AnalyticUnit.AnalyticUnitStatus.READY);
+    await Detection.insertSpan(
+      new Detection.DetectionSpan(
+        id,
+        range.from + intersection,
+        range.to - intersection,
+        Detection.DetectionStatus.READY
+      )
+    );
   } catch(err) {
-    let message = err.message || JSON.stringify(err);
-    await AnalyticUnit.setStatus(id, AnalyticUnit.AnalyticUnitStatus.FAILED, message);
+    // TODO: maybe we don't need to update detectionTime with previous value?
     if(previousLastDetectionTime !== undefined) {
       await AnalyticUnit.setDetectionTime(id, previousLastDetectionTime);
     }
+    let message = err.message || JSON.stringify(err);
+    await AnalyticUnit.setStatus(id, AnalyticUnit.AnalyticUnitStatus.FAILED, message);
+    await Detection.insertSpan(
+      new Detection.DetectionSpan(
+        id,
+        range.from + intersection,
+        range.to - intersection,
+        Detection.DetectionStatus.FAILED
+      )
+    );
   }
 }