How to configure SSH authentication key for SFTP file synchronization to connect from Acumatica to my local server.

Hi 

i am trying to connect to my local sftp server from acumatica. i have followed the instruction provided here

however. i am still getting error “Permission denied (publickey).”. i am very sure my stfp configuration is correct because i can connect to it using winSCP without any hitch. can someone please give me a more detailed way to sort this out. all the instruction i have found so far are vague and no response to follow up questions