code: private void onPublicKeysGroupRemoved(int uid, int keyGroupId) {
          UserKeys userKeys = getCachedUserKeys(uid);
          if (userKeys == null) {
              return;
          }
  
          UserKeys updatedUserKeys = userKeys.removeUserKeyGroup(keyGroupId);
          cacheUserKeys(updatedUserKeys);
          context().getEncryption().getEncryptedChatManager(uid)
                  .send(new EncryptedPeerActor.KeyGroupUpdated(userKeys));
      }
docs: Handler for removing key group
  
  @param uid        User's id
  @param keyGroupId Removed key group id