Golang wrong http resquest header

I'm building 2 apis. One make request to another.

To call the api that receives requests, we need to pass a X-Token Header. I'm doing this with Golang

client := &http.Client{
    Transport: &http.Transport{
        TLSClientConfig: &tls.Config{
            InsecureSkipVerify: true,
        },
    },
}

req, err := http.NewRequest("GET", "https://localhost:8086/v2/example", nil)
if err != nil {
    c.JSON(http.StatusInternalServerError, gin.H{"Error": err.Error()})
}
req.Header.Add("accept", "application/json")
req.Header.Add("content-type", "application/json")
req.Header.Add("x-token", "a2e63ee01401aaeca78be023dfbb8c59")

resp, err := client.Do(req)

In the other API, i get the http header with gin like this:

token := c.Request.Header.Get("x-token")

I dont know why my header arrives with another value and no X-Token. Thanks!

Result of fmt.Printf("%+v", c.Request.Header):

map[User-Agent:[Go-http-client/1.1] Referer:[https://localhost:8086/v2/example] Accept-Encoding:[gzip]]

I don't know where is my x-token, accept and content-type headers....

IMPORTANT

• If i make a request with x-token header on Postman to the requested API i get the right header.
• If i change the request address on the API that makes requests, e.g httpbin, i get the right header too....