diff --git a/main.go b/main.go
index a3a2ccf..9a34f14 100644
--- a/main.go
+++ b/main.go
@@ -350,7 +350,14 @@ func (br *bridge) publish(n *notification) error {
 			}
 
 			hash := sha512.Sum512(rawCerts[0])
-			return fmt.Errorf("ntfy certificate fingerprint does not match: expected %q, got %q", hex.EncodeToString(hash[:]), configFingerprint)
+			var expectedFingerprint string
+			for i, b := range hash {
+				if i != 0 {
+					expectedFingerprint += ":"
+				}
+				expectedFingerprint += fmt.Sprintf("%02X", b)
+			}
+			return fmt.Errorf("ntfy certificate fingerprint does not match: expected %q, got %q", expectedFingerprint, br.cfg.Ntfy.CertFingerprint)
 		}
 
 		tlsCfg.InsecureSkipVerify = true