diff --git a/build-deb/taskmanager/DEBIAN/control b/build-deb/taskmanager/DEBIAN/control
index c18d91d..0f953e2 100644
--- a/build-deb/taskmanager/DEBIAN/control
+++ b/build-deb/taskmanager/DEBIAN/control
@@ -8,4 +8,4 @@ Depends: gunicorn, python3-flask-sqlalchemy
 Homepage: https://gitea.dmz.rs/Decentrala/taskmanager
 Maintainer: Decentrala <dmz@dmz.rs>
 Description: Interactive TODO list Web app
-Version: 1.0.3
+Version: 1.0.5
diff --git a/taskmanager/routes.py b/taskmanager/routes.py
index 25775f3..05fba99 100644
--- a/taskmanager/routes.py
+++ b/taskmanager/routes.py
@@ -107,6 +107,13 @@ def project(task_id:int):
             return 'User not found, please <a href="/register">register</a>.'
         if userid is None:
             return 'User not found, please <a href="/register">register</a>.'
+        # check if user already added
+        try:
+            existinguser = TaskUser.query.filter_by(userid = userid, taskid = taskid ).first().userid
+        except:
+            existingusers = None
+        if existingusers == userid :
+            return "User already added"
         sqladduser = TaskUser(userid = userid, taskid = task_id)
         try:
             db.session.add(sqladduser)