diff --git a/part2/2.15-2.20/db.json b/part2/2.15-2.20/db.json
index dbe0b15..090004a 100644
--- a/part2/2.15-2.20/db.json
+++ b/part2/2.15-2.20/db.json
@@ -1,35 +1,5 @@
 {
   "persons": [
-    {
-      "name": "THuan",
-      "number": "22",
-      "id": 5
-    },
-    {
-      "name": "Th",
-      "number": "32049324324",
-      "id": 6
-    },
-    {
-      "name": "TTTTT",
-      "number": "32432432432",
-      "id": 7
-    },
-    {
-      "name": "TTTTTT",
-      "number": "111111",
-      "id": 8
-    },
-    {
-      "name": "Huy",
-      "number": "987654321",
-      "id": 9
-    },
-    {
-      "name": "Thao",
-      "number": "0988289099",
-      "id": 10
-    },
     {
       "name": "Minh",
       "number": "092",
@@ -84,6 +54,11 @@
       "name": "Tuan34",
       "number": "324324",
       "id": 21
+    },
+    {
+      "name": "Thuan",
+      "number": "3049324324",
+      "id": 22
     }
   ]
 }
\ No newline at end of file
diff --git a/part2/2.15-2.20/src/App.js b/part2/2.15-2.20/src/App.js
index eee3f81..685c47a 100644
--- a/part2/2.15-2.20/src/App.js
+++ b/part2/2.15-2.20/src/App.js
@@ -74,12 +74,24 @@ const App = () => {
     else {
       const result = window.confirm(`${newName} is already added to phonebook. Replace with new Number?`)
       console.log(id)
+      const person = persons.find(n => n.id === id)
       if (result) {
         Contact
           .updateContact(id, newPerson)
           .then(response => {
             setPersons(persons.map(person => person.id !== id ? person : response))
           })
+          .catch(error => {
+            setErrorMessage(
+              `Information of ${person.name} was already removed from server`
+            )
+            setErrorType('error')
+            setTimeout(() => {
+              setErrorMessage(null)
+              setErrorType (null)
+            }, 5000)
+            setPersons(persons.filter(n => n.id !== id))
+          })
       }
     }