Wechat cloud development transfer value judgment problem

Why does this code only report an error when the account is the same as the database, but not when the account is different?

            submit() {
                this.$refs.uLogin.validate().then(res => {
                uni.$u.toast('正在登录')
                
                    this.isConfirm = false;
                    setTimeout(() => {
                        this.isConfirm = true
                        const db = wx.cloud.database()
                        let vm = this
                        db.collection('userAccounts').where({
                            user:vm.login.userInfo.user,
                            
                        }).get({
                            success: function(res) {
                                
                                if((res.data[0].password==vm.login.userInfo.password)&&(res.data[0].user==vm.login.userInfo.user)){
                                    uni.$u.toast('欢迎回家！');
                                }else{
                                    uni.$u.toast('账号或密码错误！');
                                }
                                
                            }
                        })
                        // 这里此提示会被this.start()方法中的提示覆盖
                    
                        // 通知验证码组件内部开始倒计时

                    }, 2000);
                    // this.isConfirm=false;
                }).catch(errors => {
                    this.isConfirm = false;
                    setTimeout(() => {
                        this.isConfirm = true
                        // 这里此提示会被this.start()方法中的提示覆盖
                        uni.$u.toast('账号或密码错误');
                        // 通知验证码组件内部开始倒计时

                    }, 2000);
                })
            },