diff --git a/internal/provider/diagnostics.go b/internal/provider/diagnostics.go
index b2ebd3d..2948770 100644
--- a/internal/provider/diagnostics.go
+++ b/internal/provider/diagnostics.go
@@ -2,6 +2,7 @@ package provider
 
 import (
 	"errors"
+	"strings"
 
 	"github.com/dynu/terraform-provider-dynu/internal/dynuclient"
 )
@@ -16,7 +17,11 @@ func diagnosticSummary(defaultSummary string, err error) string {
 	case 401, 403:
 		return defaultSummary + " (authentication failed)"
 	case 404:
-		return defaultSummary + " (not found)"
+		normalizedType := strings.ToLower(strings.TrimSpace(apiErr.Type))
+		if strings.Contains(normalizedType, "not found") {
+			return defaultSummary + " (not found)"
+		}
+		return defaultSummary
 	default:
 		return defaultSummary
 	}
diff --git a/internal/provider/provider_test.go b/internal/provider/provider_test.go
index 84479bb..c237f4e 100644
--- a/internal/provider/provider_test.go
+++ b/internal/provider/provider_test.go
@@ -67,6 +67,7 @@ func TestDiagnosticSummary(t *testing.T) {
 		{name: "non api error", err: os.ErrNotExist, summary: "Unable to list Dynu domains", want: "Unable to list Dynu domains"},
 		{name: "auth error", err: &dynuclient.APIError{StatusCode: 401, Type: "Unauthorized", Message: "invalid"}, summary: "Unable to list Dynu domains", want: "Unable to list Dynu domains (authentication failed)"},
 		{name: "not found", err: &dynuclient.APIError{StatusCode: 404, Type: "Not Found", Message: "missing"}, summary: "Unable to resolve Dynu domain from hostname", want: "Unable to resolve Dynu domain from hostname (not found)"},
+		{name: "404 validation exception", err: &dynuclient.APIError{StatusCode: 404, Type: "Request Exception", Message: "Invalid."}, summary: "Unable to update Dynu DNS record", want: "Unable to update Dynu DNS record"},
 	}
 
 	for _, tc := range tests {