我在通过连接FTP路径进行文件传输时收到以下错误Mulesoft代码已经工作了很多天，不幸的是，我们从几个dys。所以请帮我解决这个问题。
错误
Message: An exception was found trying to obtain a connection: Found exception trying to change transfer mode to class org.mule.extension.ftp.api.ftp.FtpTransferMode. FTP reply code is: 421
Element : ac-ngwtransform-ftp-v1Flow/processors/6/processors/0/route/0/processors/1 @ azx-us-int-ac-ngwtransform-ftp-v1:ac-ngwtransform-ftp-v1.xml:84 (Reading the file from FTP)
Element XML : <ftp:read doc:name="Reading the file from FTP" doc:id="da9be7af-d84b-4a78-a8ce-cd9f117aa273" config-ref="FTP_Config_NGW" path="#[attributes.fileName]" outputMimeType="text/plain"></ftp:read>
Error type : FTP:CONNECTIVITY
Payload Type : org.mule.runtime.core.internal.streaming.bytes.ManagedCursorStreamProvider
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Root Exception stack trace:
org.apache.commons.net.ftp.FTPConnectionClosedException: FTP response 421 received.
您可以使用重新连接策略来解决此问题。转到您的ftp连接器-->前进->单击重新连接并使重新连接策略成为标准。