diff --git a/SCRUM-Timer/CountdownTimer.cs b/SCRUM-Timer/CountdownTimer.cs
index 138eec1..5a38e8e 100644
--- a/SCRUM-Timer/CountdownTimer.cs
+++ b/SCRUM-Timer/CountdownTimer.cs
@@ -12,7 +12,6 @@ public class CountdownTimer
     public CountdownTimer()
     {
         ActualTime = new TimeSpan(0, 5, 0);
-        timerThread = new Thread(TimerTick);
         isRunning = false;
     }
 
@@ -20,13 +19,13 @@ public class CountdownTimer
     {
         if (!isRunning)
         {
+            timerThread = new Thread(TimerTick);
             timerThread.Start();
             isRunning = true;
             Console.WriteLine("Timer is running");
         }
         else
         {
-            timerThread.Abort();
             isRunning = false;
             Console.WriteLine("Timer is stopped");
         }
@@ -34,11 +33,17 @@ public class CountdownTimer
 
     private void TimerTick()
     {
+        TimeSpan tickTime = new TimeSpan(0,0,1);
         while (isRunning)
         {
-            ActualTime = -TimeSpan.FromSeconds(1);
-            Thread.Sleep(1000);
+            ActualTime = ActualTime.Subtract(tickTime);
             Console.WriteLine(ActualTime);
+            Thread.Sleep(1000);
         }
     }
+
+    public void AddTime(TimeSpan time)
+    {
+        ActualTime = ActualTime.Add(time);
+    }
 }
\ No newline at end of file
diff --git a/SCRUM-Timer/Views/MainWindow.axaml.cs b/SCRUM-Timer/Views/MainWindow.axaml.cs
index 5ed3a9c..233a4e2 100644
--- a/SCRUM-Timer/Views/MainWindow.axaml.cs
+++ b/SCRUM-Timer/Views/MainWindow.axaml.cs
@@ -1,3 +1,4 @@
+using System;
 using Avalonia.Controls;
 using Avalonia.Interactivity;
 
@@ -14,12 +15,12 @@ public partial class MainWindow : Window
 
     private void ButtonHandlerStartStop(object? sender, RoutedEventArgs e)
     {
-        
         countdownTimer.StartStop();
     }
 
     private void ButtonHandlerAddTime(object? sender, RoutedEventArgs e)
     {
-        throw new System.NotImplementedException();
+        var time = new TimeSpan(0, 1, 0);
+        countdownTimer.AddTime(time);
     }
 }
\ No newline at end of file
diff --git a/SCRUM-Timer/bin/Debug/net9.0/SCRUM-Timer.dll b/SCRUM-Timer/bin/Debug/net9.0/SCRUM-Timer.dll
index b85484f..d496e4f 100644
Binary files a/SCRUM-Timer/bin/Debug/net9.0/SCRUM-Timer.dll and b/SCRUM-Timer/bin/Debug/net9.0/SCRUM-Timer.dll differ
diff --git a/SCRUM-Timer/bin/Debug/net9.0/SCRUM-Timer.pdb b/SCRUM-Timer/bin/Debug/net9.0/SCRUM-Timer.pdb
index f59fb69..2e54727 100644
Binary files a/SCRUM-Timer/bin/Debug/net9.0/SCRUM-Timer.pdb and b/SCRUM-Timer/bin/Debug/net9.0/SCRUM-Timer.pdb differ
diff --git a/SCRUM-Timer/obj/Debug/net9.0/SCRUM-Timer.AssemblyInfo.cs b/SCRUM-Timer/obj/Debug/net9.0/SCRUM-Timer.AssemblyInfo.cs
index c81f5ad..e089a15 100644
--- a/SCRUM-Timer/obj/Debug/net9.0/SCRUM-Timer.AssemblyInfo.cs
+++ b/SCRUM-Timer/obj/Debug/net9.0/SCRUM-Timer.AssemblyInfo.cs
@@ -13,7 +13,7 @@ using System.Reflection;
 [assembly: System.Reflection.AssemblyCompanyAttribute("SCRUM-Timer")]
 [assembly: System.Reflection.AssemblyConfigurationAttribute("Debug")]
 [assembly: System.Reflection.AssemblyFileVersionAttribute("1.0.0.0")]
-[assembly: System.Reflection.AssemblyInformationalVersionAttribute("1.0.0+b5f040711a695687b09539793d3519f026ba40a7")]
+[assembly: System.Reflection.AssemblyInformationalVersionAttribute("1.0.0+e6c95330185fd51fe629aa915eb1cb4d946479ca")]
 [assembly: System.Reflection.AssemblyProductAttribute("SCRUM-Timer")]
 [assembly: System.Reflection.AssemblyTitleAttribute("SCRUM-Timer")]
 [assembly: System.Reflection.AssemblyVersionAttribute("1.0.0.0")]
diff --git a/SCRUM-Timer/obj/Debug/net9.0/SCRUM-Timer.AssemblyInfoInputs.cache b/SCRUM-Timer/obj/Debug/net9.0/SCRUM-Timer.AssemblyInfoInputs.cache
index e3cd784..9e41bad 100644
--- a/SCRUM-Timer/obj/Debug/net9.0/SCRUM-Timer.AssemblyInfoInputs.cache
+++ b/SCRUM-Timer/obj/Debug/net9.0/SCRUM-Timer.AssemblyInfoInputs.cache
@@ -1 +1 @@
-14bfb30c3cc6894a87173643d24f061b81e75980cb90329f56da8a0470ff5201
+36fe41ba478871ad1527db68f03d4bce7e4a81176581ac14b5ce7d0b7638a0e8
diff --git a/SCRUM-Timer/obj/Debug/net9.0/SCRUM-Timer.dll b/SCRUM-Timer/obj/Debug/net9.0/SCRUM-Timer.dll
index b85484f..d496e4f 100644
Binary files a/SCRUM-Timer/obj/Debug/net9.0/SCRUM-Timer.dll and b/SCRUM-Timer/obj/Debug/net9.0/SCRUM-Timer.dll differ
diff --git a/SCRUM-Timer/obj/Debug/net9.0/SCRUM-Timer.pdb b/SCRUM-Timer/obj/Debug/net9.0/SCRUM-Timer.pdb
index f59fb69..2e54727 100644
Binary files a/SCRUM-Timer/obj/Debug/net9.0/SCRUM-Timer.pdb and b/SCRUM-Timer/obj/Debug/net9.0/SCRUM-Timer.pdb differ
diff --git a/SCRUM-Timer/obj/Debug/net9.0/ref/SCRUM-Timer.dll b/SCRUM-Timer/obj/Debug/net9.0/ref/SCRUM-Timer.dll
index bbd3712..b01b5cd 100644
Binary files a/SCRUM-Timer/obj/Debug/net9.0/ref/SCRUM-Timer.dll and b/SCRUM-Timer/obj/Debug/net9.0/ref/SCRUM-Timer.dll differ
diff --git a/SCRUM-Timer/obj/Debug/net9.0/refint/SCRUM-Timer.dll b/SCRUM-Timer/obj/Debug/net9.0/refint/SCRUM-Timer.dll
index bbd3712..b01b5cd 100644
Binary files a/SCRUM-Timer/obj/Debug/net9.0/refint/SCRUM-Timer.dll and b/SCRUM-Timer/obj/Debug/net9.0/refint/SCRUM-Timer.dll differ