diff --git a/donate.py b/donate.py
index 4a57279d..fd53936f 100644
--- a/donate.py
+++ b/donate.py
@@ -51,6 +51,20 @@ def setDonationUrl(actorJson: {},donateUrl: str) -> None:
     if not donateName:
         return
 
+    # remove any existing value
+    propertyFound=None
+    for propertyValue in actorJson['attachment']:
+        if not propertyValue.get('name'):
+            continue
+        if not propertyValue.get('type'):
+            continue
+        if not propertyValue['name'].lower()!=donateName:
+            continue
+        propertyFound=propertyValue
+        break
+    if propertyFound:
+        actorJson['attachment'].remove(propertyFound)
+
     donateValue='<a href="'+donateUrl+'" rel="me nofollow noopener noreferrer" target="_blank">'+donateUrl+'</a>'
 
     for propertyValue in actorJson['attachment']:
diff --git a/matrix.py b/matrix.py
index 017a85e6..61835f59 100644
--- a/matrix.py
+++ b/matrix.py
@@ -41,6 +41,20 @@ def setMatrixAddress(actorJson: {},matrixAddress: str) -> None:
     if not actorJson.get('attachment'):
         actorJson['attachment']=[]
 
+    # remove any existing value
+    propertyFound=None
+    for propertyValue in actorJson['attachment']:
+        if not propertyValue.get('name'):
+            continue
+        if not propertyValue.get('type'):
+            continue
+        if not propertyValue['name'].lower().startswith('matrix'):
+            continue
+        propertyFound=propertyValue
+        break
+    if propertyFound:
+        actorJson['attachment'].remove(propertyFound)
+
     if '@' not in matrixAddress:
         return
     if not matrixAddress.startswith('@'):
diff --git a/pgp.py b/pgp.py
index d4a1ef81..62679319 100644
--- a/pgp.py
+++ b/pgp.py
@@ -58,6 +58,20 @@ def setEmailAddress(actorJson: {},emailAddress: str) -> None:
     if not actorJson.get('attachment'):
         actorJson['attachment']=[]
 
+    # remove any existing value
+    propertyFound=None
+    for propertyValue in actorJson['attachment']:
+        if not propertyValue.get('name'):
+            continue
+        if not propertyValue.get('type'):
+            continue
+        if not propertyValue['name'].lower().startswith('email'):
+            continue
+        propertyFound=propertyValue
+        break
+    if propertyFound:
+        actorJson['attachment'].remove(propertyFound)
+
     if '@' not in emailAddress:
         return
     if '.' not in emailAddress:
@@ -90,6 +104,20 @@ def setPGPpubKey(actorJson: {},PGPpubKey: str) -> None:
     if not actorJson.get('attachment'):
         actorJson['attachment']=[]
 
+    # remove any existing value
+    propertyFound=None
+    for propertyValue in actorJson['attachment']:
+        if not propertyValue.get('name'):
+            continue
+        if not propertyValue.get('type'):
+            continue
+        if not propertyValue['name'].lower().startswith('pgp'):
+            continue
+        propertyFound=propertyValue
+        break
+    if propertyFound:
+        actorJson['attachment'].remove(propertyValue)
+
     if '--BEGIN PGP PUBLIC KEY' not in PGPpubKey:
         return
 
diff --git a/xmpp.py b/xmpp.py
index 667669cf..13b4e995 100644
--- a/xmpp.py
+++ b/xmpp.py
@@ -39,6 +39,21 @@ def setXmppAddress(actorJson: {},xmppAddress: str) -> None:
     if not actorJson.get('attachment'):
         actorJson['attachment']=[]
 
+    # remove any existing value
+    propertyFound=None
+    for propertyValue in actorJson['attachment']:
+        if not propertyValue.get('name'):
+            continue
+        if not propertyValue.get('type'):
+            continue
+        if not (propertyValue['name'].lower().startswith('xmpp') or \
+                propertyValue['name'].lower().startswith('jabber')):
+            continue
+        propertyFound=propertyValue
+        break
+    if propertyFound:
+        actorJson['attachment'].remove(propertyFound)
+
     if '@' not in xmppAddress:
         return
     if '.' not in xmppAddress: