List SFTP Processor doesn't lists the files in Apache Nifi

[#1]

Nifi Version- 1.7.1
List SFTP Processor doesn't lists the files when run via CRON jobs/Schedule even though the file is available.
We even see that List SFTP has run.

On doing a restart of process(STOP,change schedule,START) the List SFTP Processor picks up the file.
Can someone suggest on the root cause and let us know how to fix it as these were working fine before.

[#2]

@ShrutiNifi Welcome to the Cloudera Community!

To help you get the best possible solution, I have tagged our NiFi expert @steven-matison  who may be able to assist you further.

Please keep us updated on your post, and we hope you find a satisfactory solution to your query.