Spring WebSocket: How to reject group message but still send error to /queue/errors/{userId}?

I would like to send message to /queue/errors/{userId}, when user is not in the group and also I would like to reject message to group. Problem is how to send message to /queue/errors/{userId} without sending them to /queue/group/{groupId}. While I return null when user is not in the group I can't send message to /queue/errors/{userId} because all messages are reject. I have logs:

2025-07-13T10:02:47.759Z  WARN 1 --- [chat-service] [nio-8082-exec-2] o.w.c.c.WebSocketAuthChannelInterceptor  : User not in group!
2025-07-13 12:02:47 2025-07-13T10:02:47.761Z DEBUG 1 --- [chat-service] [nio-8082-exec-2] o.s.m.s.b.SimpleBrokerMessageHandler     : Processing MESSAGE destination=/queue/errors/11 session=null payload=You are not a member of group!
2025-07-13 12:02:47 2025-07-13T10:02:47.764Z DEBUG 1 --- [chat-service] [nio-8082-exec-2] o.s.m.s.ExecutorSubscribableChannel      : WebSocketAuthChannelInterceptor returned null from preSend, i.e. precluding the send.

@Slf4j
@Component
@RequiredArgsConstructor
public class WebSocketAuthChannelInterceptor implements ChannelInterceptor {

    private final JwtService jwtService;
    private final GroupService groupService;

    private SimpMessagingTemplate messagingTemplate;

    @Autowired
    public void setMessagingTemplate(@Lazy SimpMessagingTemplate messagingTemplate) {
        this.messagingTemplate = messagingTemplate;
    }

    @Override
    public Message<?> preSend(Message<?> message, MessageChannel channel) {
        StompHeaderAccessor accessor = MessageHeaderAccessor.getAccessor(message, StompHeaderAccessor.class);
        assert accessor != null;
        if (StompCommand.CONNECT.equals(accessor.getCommand())) {

            String token = accessor.getFirstNativeHeader("Authorization");

            if (token == null || !token.startsWith("Bearer ")) {
                log.warn("No token provided or invalid format!");
                return null;
            }

            token = token.substring(7);

            if (!jwtService.isTokenValid(token)) {
                log.warn("Invalid token");
                return null;
            }

            String groupId = accessor.getFirstNativeHeader("groupId");
            long userId = jwtService.extractId(token);
            log.info("Group id: {}", groupId);

            if (!groupService.validateUserInGroup(groupId, userId)) {
                log.warn("User not in group!");
                sendErrorToUser(userId, "You are not a member of group!");
                return null;
            }

            String email = jwtService.extractEmail(token);
            List<String> roles = jwtService.extractRoles(token);

            Authentication authentication = new UsernamePasswordAuthenticationToken(
                    email, null, mapRolesToAuthorities(roles)
            );

            accessor.setUser(authentication);
            SecurityContextHolder.getContext().setAuthentication(authentication);

            log.info("User is authorized by WebSocket: {}", email);
            return message;
        }

        return message;
    }

    private Collection<? extends GrantedAuthority> mapRolesToAuthorities(List<String> roles) {
        return roles.stream()
                .map(role -> new SimpleGrantedAuthority("ROLE_" + role))
                .collect(Collectors.toList());
    }


    private void sendErrorToUser(long userId, String errorMsg) {
        String destination = "/queue/errors/" + userId;
        messagingTemplate.convertAndSend(destination, errorMsg);
    }
}