ReactiveMongoDatabase:如何预先创建集合:无法在多文档事务中创建命名空间

@SpringBootTest

bean是(如果我想使用reactive,那么这就是我应该使用的bean?)

    @Bean
    Mono<MongoDatabase> reactiveMongoDatabase() {
        // recommended way in ReactiveMongoTransactionManager javadoc
        log.info("Creating reactiveMongoDatabase...");
        return ReactiveMongoDatabaseUtils.getDatabase(properties.getDatabase(), reactiveMongoDatabaseFactory());
    }

    @Autowired
    private ReactiveMongoTemplate template;

    @BeforeEach
    private void createColletion() {
        //mongoDatabase.createCollection("Coupon");
        template.createCollection(Coupon.class);
    }

[ENV=itest] [productName=promotion-facts-sync] [2020-03-19T14:26:09.801Z] [ERROR] [MSG=[Thread-20] e.v.c.p.f.service.SyncProcessService - Error while processing empty message. Cause: Cannot create namespace promotion-facts-sync.Coupon in multi-document transaction.; nested exception is com.mongodb.MongoWriteException: Cannot create namespace promotion-facts-sync.Coupon in multi-document transaction. ][TRACE=] [SPAN=]

怎么做?