diff --git a/main.go b/main.go
index 183f966..0ba3657 100644
--- a/main.go
+++ b/main.go
@@ -35,12 +35,11 @@ func main() {
 	}
 	insecure, _ := strconv.ParseBool(gha.GetInput("insecure"))
 	if tagName == "" {
+		if !strings.HasPrefix(ctx.Ref, "refs/tags/") {
+			gha.Fatalf("ref %s is not a tag", ctx.Ref)
+		}
 		tagName = ctx.RefName
 	}
-// I don't understend what this doing
-//	if !strings.HasPrefix(tagName, "refs/tags/") {
-//		gha.Fatalf("ref %s is not a tag", tagName)
-//	}
 
 	client := http.DefaultClient
 	if insecure {