我正在使用虚拟环境运行Mac。我创建了一个airflow文件夹和airflow_home子文件夹。在我的airflow_home文件夹中，有一个名为dag的子文件夹。
我正在输入以下命令行来运行气流服务器：
source airflow/bin/activate
cd airflow
export AIRFLOW_HOME=\`pwd\`/airflow_home
airflow webserver
airflow scheduler
输入airflow webserver时出现以下错误：
/Users/username/Desktop/virtualenvs/airflow/lib/python3.6/site-packages/airflow/configuration.py:652: DeprecationWarning: You have two airflow.cfg files: /Users/username/airflow/airflow.cfg and /Users/username/Desktop/virtualenvs/airflow/airflow_home/airflow.cfg. Airflow used to look at ~/airflow/airflow.cfg, even when AIRFLOW_HOME was set to a different value. Airflow will now only read /Users/username/Desktop/virtualenvs/airflow/airflow_home/airflow.cfg, and you should remove the other file category=DeprecationWarning
现在从气流UI出现此错误：
The scheduler does not appear to be running. Last heartbeat was received 2 minutes ago.
The DAGs list may not update, and new tasks will not be scheduled.
，实际上在创建新的dag时，它们不会出现在UI中。
我该怎么办？