3822849 - SFTP - Files are not getting decrypted in SAP PI

When the files are being decrypted by the SAP PI application, the clients see the following error : 

com.sap.esb.camel.security.pgp.PgpException: An exception occurred during decrypting/verifiyng a PGP message. The PGP message may have been tampered. Reason: The input message body has an invalid format. The PGP decryption/verification processor expects a sequence of PGP packets of the form (entries in brackets are optional and ellipses indicate repetition, comma represents sequential composition, and vertical bar separates alternatives): Public Key Encrypted Session Key ..., Symmetrically Encrypted Data | Sym. Encrypted and Integrity Protected Data, Compressed Data, (One Pass Signature ...,) Literal Data, (Signature ...,), cause: iaik.pgp.exceptions.PGPParsingException: Read invalid packet (ONE_PASS_SIGNATURE (TAG 4)) while decoding iaik.pgp.transferables.PGPMessage

files sent to the SFTP folder are picked up by the SAP PI and then decrypted for processing. Clients encounter error when decrypting the files , KBA , CON-CA-TLS-IEM-JOB , Scheduled Jobs , Problem