Upload file in POST request

Hi, I have problem with uploading files from my script, here are two screenshots from Fiddler when I upload file via browser:

And here are when I run gatling

Here are code fragments with header Map and the request when I teoratically upload file:

.exec(http("request_30") .options("/api/media/images") .headers(headers_30) .resources(http("request_31") .post("/api/media/images") .check(regex("""[\w\d]{8}-[\w\d]{4}-[\w\d]{4}-[\w\d]{4}-[\w\d]{12}""").find.saveAs("photoId")) .headers(headers_31) .body(RawFileBody("recordedsimulation/0031_request.dat")))) .exec(http("request_32") .get("/UploadedFiles/${photoId}.png") .headers(headers_9))

`
val headers_30 = Map(
“Access-Control-Request-Headers” → “authorization”,
“Access-Control-Request-Method” → “POST”,
“Origin” → “https://frontend.iteodev.com”,
“Sec-Fetch-Mode” → “cors”)

val headers_31 = Map(
“Accept” → “application/json, text/plain, /”,
“Accept-Enconding” → “gzip, deflate, br”,
“Content-Type” → “multipart/form-data; boundary=----WebKitFormBoundarycByzqwKAVKTwQR0H”,
“Origin” → “https://frontend.iteodev.com”,
“Sec-Fetch-Mode” → “cors”,
“authorization” → “Bearer ${authToken}”)

`

And the content of .dat file

------WebKitFormBoundarycByzqwKAVKTwQR0H Content-Disposition: form-data; name="file"; filename="photo.png" Content-Type: image/png

What should I add or change to upload my file? Thanks in advance