diff --git a/lib/shared/id-utils.js b/lib/shared/id-utils.js
--- a/lib/shared/id-utils.js
+++ b/lib/shared/id-utils.js
@@ -163,6 +163,10 @@
   return userID.replace(farcasterUserIDPrefix, '');
 }
 
+function isFarcasterUserID(userID: string): boolean {
+  return userID.startsWith(farcasterUserIDPrefix);
+}
+
 function farcasterPersonalConversationID(
   user1FID: number | string,
   user2FID: number | string,
@@ -192,4 +196,5 @@
   extractFIDFromUserID,
   farcasterPersonalConversationID,
   getFIDFromUserID,
+  isFarcasterUserID,
 };
diff --git a/lib/shared/relationship-utils.js b/lib/shared/relationship-utils.js
--- a/lib/shared/relationship-utils.js
+++ b/lib/shared/relationship-utils.js
@@ -2,6 +2,7 @@
 
 import invariant from 'invariant';
 
+import { isFarcasterUserID } from './id-utils.js';
 import {
   type RelationshipButton,
   type UserRelationshipStatus,
@@ -27,8 +28,11 @@
 }
 
 function getAvailableRelationshipButtons(
-  userInfo: UserInfo,
+  userInfo: ?UserInfo,
 ): RelationshipButton[] {
+  if (!userInfo || isFarcasterUserID(userInfo.id)) {
+    return [];
+  }
   const relationship = userInfo.relationshipStatus;
 
   if (relationship === userRelationshipStatus.FRIEND) {
diff --git a/native/chat/settings/thread-settings-edit-relationship.react.js b/native/chat/settings/thread-settings-edit-relationship.react.js
--- a/native/chat/settings/thread-settings-edit-relationship.react.js
+++ b/native/chat/settings/thread-settings-edit-relationship.react.js
@@ -12,6 +12,7 @@
   getRelationshipDispatchAction,
 } from 'lib/shared/relationship-utils.js';
 import { getSingleOtherUser } from 'lib/shared/thread-utils.js';
+import { stringForUserExplicit } from 'lib/shared/user-utils.js';
 import type { ThreadInfo } from 'lib/types/minimally-encoded-thread-permissions-types.js';
 import {
   type TraditionalRelationshipAction,
@@ -88,8 +89,7 @@
     const { panelIosHighlightUnderlay } = colors;
 
     const styles = useStyles(unboundStyles);
-    const otherUserInfoUsername = otherUserInfo.username;
-    invariant(otherUserInfoUsername, 'Other user username should be specified');
+    const otherUserInfoUsername = stringForUserExplicit(otherUserInfo);
 
     const relationshipButtonText = React.useMemo(
       () =>