Problem with SAML time validation

Problem with SAML time validation

From our application we do a SAML request using accounts.zohoportal.eu/accounts request to log our users in into the customer portal in zoho.desk.
This has always worked until this morning. We now get the following error: Conditions validation failed.

During debugging I found out that if I wait for a bit longer, the request is processed as normal which led me to some tweaking. Normally we add the following condition  but this lead to request being invalid.
  1. ->setNotBefore(new \DateTime()
However I changed it to
  1. ->setNotBefore(new \DateTime("-5 seconds")
All the requests were performed as expected, which leads me to believe there is a problem in the time settings on the server? Did something change in the validation of the SAML request?