I tried to set up the "Inventory Subscription API" but when I try to test it I get the following error:
"I/O error on POST request for \"">inventory.********/.../InventoryNotification.php\": PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target; nested exception is javax.net.ssl.SSLHandshakeException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target"
We use a certificate from Let's Encrypt / R3. Could this be an issue?