diff --git a/main.go b/main.go
index ac69551..c12b86b 100644
--- a/main.go
+++ b/main.go
@@ -126,13 +126,6 @@ func Run(ctx context.Context, config string) error {
 		if err != nil {
 			return fmt.Errorf("encounted error while creating request: %v", err.Error())
 		}
-		if strings.Contains(conf.Headers, ";") {
-			for _, element := range strings.Split(conf.Headers, ";") {
-				req.Header.Add(strings.Split(element, ":")[0], strings.Split(element, ":")[1])
-			}
-		} else {
-			req.Header.Add(strings.Split(conf.Headers, ":")[0], strings.Split(conf.Headers, ":")[1])
-		}
 
 	} else {
 		req, err = http.NewRequestWithContext(ctx, requestType, conf.URL, bytes.NewBufferString(conf.Body))
@@ -142,6 +135,25 @@ func Run(ctx context.Context, config string) error {
 		req.Header.Add("Content-Type", conf.ContentType)
 	}
 
+	if conf.Headers != "" {
+		if strings.Contains(conf.Headers, ";") {
+			headers := strings.Split(conf.Headers, ";")
+			for _, element := range headers {
+				keyvalue := strings.Split(element, ":")
+				if len(keyvalue) != 2 {
+					return fmt.Errorf("header format must be \"header:value;header:value\" ; got: %v", conf.Headers)
+				}
+				req.Header.Add(keyvalue[0], keyvalue[1])
+			}
+		} else {
+			keyvalue := strings.Split(conf.Headers, ":")
+			if len(keyvalue) != 2 {
+				return fmt.Errorf("header format must be \"header:value;header:value\" ; got: %v", conf.Headers)
+			}
+			req.Header.Add(keyvalue[0], keyvalue[1])
+		}
+	}
+
 	tls_config := &tls.Config{InsecureSkipVerify: conf.Insecure}
 	http_transpot := &http.Transport{TLSClientConfig: tls_config}
 	client := &http.Client{Transport: http_transpot}