Hi Chandra ,
Which type of SSL is your webservice provider expecting :
is it Two Way SSL with Basic Authentication ? or One way SSL with Basic Authentication ?
If it’s two way SSL then both Client and Server should validate each other based on their certificates .
If it’s one way SSL , only client needs to validate the server based on server certificate.
Please check with your webservice provider .
You can debug the SSL connection and find out exactly where is the issue ?
You can refer to the below link for debugging SSL connections on Integration Server.