Content-Type头会出现2次。这个到底是什么问题

无法发图片出来无法发图片出来无法发图片出来

ContentType = ContentType or "application/x-www-form-urlencoded; charset=utf-8"

    local header = {
    }
    header["Content-Type"] = "application/x-www-form-urlencoded"
    local data, status= net.http.post(u, header, body, Global.TimeOut)
    return data, status
    
    
    
    Accept: */*

Accept-Language: zh-CN,zh;q=0.9
Content-Type: application/x-www-form-urlencoded
Content-Type:
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.114 Safari/537.36 Edg/91.0.864.54
Connection: close
Content-Length: 4430
Host: *

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