> For the complete documentation index, see [llms.txt](https://doc.vietqr.vn/doc/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.vietqr.vn/doc/api-vietqr-callback/hoi-dap-api.md).

# Hỏi đáp API

Hỏi :  Hệ thống báo Lỗi  <mark style="color:red;">string(35) "{"status":"FAILED","message":"E34"}"</mark> là ggì?&#x20;

Trả lời : &#x20;

LỗLỗi này là <mark style="color:purple;">"orderId" không vượt quá 13 ký tự và "content" không vượt quá 19 ký tự</mark>,

Anh/chchị check lại format giúp em!


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