This behavior occurs when you try to run the SSIS package by using a different computer or a different user account than the computer and user account that were used to create the SSIS package.
To resolve this behavior, change the value of the ProtectionLevel property in the SSIS package.
More details you may refer the official documentations:
If the issue only occurs when you run the package via gent job, please consider to use proxy account which have the full permission to the file to run the job.
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