Hi raj
Mark as best answer, If it resloves !!​
Things to check:
- Is the delegated authentication URL correct? This can be seen in the Salesforce administration console under Security >> Single Sign-On Settings
- Check the Delegated Authentication Error History logs in Salesforce at Manage Users >> Delegated Authentication Error History
If you see a SSLPeerUnverifiedException error in the Delegated Authentication Error History, the certificate chain is missing a trusted intermediate certificate.

You can further verify the certificate chain with the following OpenSSL command:
openssl s_client -connect your.delegated.authentication.server:443 -showcerts

Fixing a missing intermediate certificate:
1. Determine which intermediate certificate was used to sign the SSL certificate.  This may be determined by noting the Issuer DN when viewing certificate details.

2. From within PingFederate, export the public-only key (for the new SSL certificate previously imported)

3. Combine the exported public key with the intermediate key for the above Verisign certificate. To do this, use the following openssl command:

openssl crl2pkcs7 -nocrl -certfile <yourSSLpublickey.cer> -certfile <intermediateca.cer> -outform PEM -out <csr_response.p7>

4) Import resulting pkcs7 file, via 'Certificate Management' -> 'Certificate Signing' (to the right of the SSL cert) -> 'Import CSR Response' and select the newly generated pkcs7 file.

5) If PingFederate does not allow the file to be imported, you may need to first import the intermediate certificate into the Trusted CA's store within PingFederate.

6) To test that PingFederate is indeed including the intermediate certificate when negotiating SSL, you may test with the following command, which should now show both the primary and intermediate certificates in the response:

openssl s_client -connect your.delegated.authentication.server:443 -showcerts


courtesy : https://ping.force.com/Support/PingFederate/Certificates/Salesforce-Delegated-Authentication-Stops-Working-with-Error-Your-company-s-authentication-service-is-currently-down

Mark as resloved if it helps :) :)
Thanks, 
Bhanu Prakash
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