public Mono<UpdateResult> updateBlockedUsers(
            @NotEmpty Set<GroupBlockedUser.@ValidGroupBlockedUserKey Key> keys,
            @Nullable @PastOrPresent Date blockDate,
            @Nullable Long requesterId) {
        try {
            Validator.notEmpty(keys, "keys");
            for (GroupBlockedUser.Key key : keys) {
                DataValidator.validGroupBlockedUserKey(key);
            }
            Validator.pastOrPresent(blockDate, "blockDate");
        } catch (ResponseException e) {
            return Mono.error(e);
        }
        if (Validator.areAllNull(blockDate, requesterId)) {
            return OperationResultPublisherPool.ACKNOWLEDGED_UPDATE_RESULT;
        }
        return groupBlocklistRepository.updateBlockedUsers(keys, blockDate, requesterId);
    }
@return whether the user to unblock was blocked
turms-service/src/main/java/im/turms/service/domain/group/service/GroupBlocklistService.java