diff --git a/app/src/main/java/de/joel/zoomhelper/Attendee.java b/app/src/main/java/de/joel/zoomhelper/Attendee.java
index f0a504f..b412c50 100644
--- a/app/src/main/java/de/joel/zoomhelper/Attendee.java
+++ b/app/src/main/java/de/joel/zoomhelper/Attendee.java
@@ -3,6 +3,7 @@ package de.joel.zoomhelper;
 import java.io.Serializable;
 
 public class Attendee implements Serializable {
+    private static final long serialVersionUID = 6196688086302483907L;
     public String name;
     public String num;
 
diff --git a/app/src/main/java/de/joel/zoomhelper/Meeting.java b/app/src/main/java/de/joel/zoomhelper/Meeting.java
index b513ace..15936fb 100644
--- a/app/src/main/java/de/joel/zoomhelper/Meeting.java
+++ b/app/src/main/java/de/joel/zoomhelper/Meeting.java
@@ -4,6 +4,7 @@ import java.io.Serializable;
 import java.util.ArrayList;
 
 public class Meeting implements Serializable {
+    private static final long serialVersionUID = 2606722401897866931L;
     public String meetingName;
     public String meetingID;
     public String meetingPWD;