saml signature validation failed

Hello,

Just wondering how do I start troubleshooting the following error:

Signature validation failed.

The Possible reasons could be :

1. It is possible that you typed the address incorrectly.
2. The URL may be invalid.

I'm using OneLogin as my IdP, have uploaded my publickey (as opposed to x509 certificate) to my zoho saml config in the control panel.

When accessing my zoho mail, it will redirect to my onelogin portal where i authenticate successfully, but the response back to zoho gives me the above error in my browser. By the way, the URL for the above error is https://accounts.zoho.com/samlresponse/hennessyp.business.zoho.com

If anybody can give me hints how to start troubleshooting that will be greatly appreciated. I've looked at this for the last 2 days and haven't gotten anywhere

Thanks in advance