Trying to upload image from Android to AWS Lambda

Question

I am using this code in Kotlin/Android to upload image to server:

fun uploadImageWithLambda(){
        val file = File(filePath)
        val retrofit = NetworkClient.getRetrofitObj()
        val uploadApis = retrofit.create(UploadApis::class.java)
        val requestBody = RequestBody.create(MediaType.parse("image/*"), file)
        val part = MultipartBody.Part.createFormData("image", file.name, requestBody)

        val call = uploadApis.uploadImage(imageRequest = part)
        call.enqueue(object : Callback<ImageResponse> {
            override fun onFailure(call: Call<ImageResponse>, t: Throwable) {
                Log.e(TAG, t.toString())
            }

            override fun onResponse(call: Call<ImageResponse>, response: Response<ImageResponse>) {
                Log.i(TAG, "success")
            }
        })

    }

This is function in UploadApis

@Multipart
@POST("prod/res")
fun uploadImage(@Part imageRequest: MultipartBody.Part) : Call<ImageResponse>

The file that I received in Lambda cannot be open. When I removed some bytes from that file I got proper image file.

First lines of code in my lambda function:

const multipart = require('aws-multipart-parser')

exports.handler = async (event) => {
    try {

        CONSTANTS.logger.info("POST image in S3...")
        let spotText = {}
        const result = multipart.parse(event, spotText)
        fs.writeFileSync('original.jpg', result.image.content)
        const content = result.image.content;
        console.log(result)

        var newBuffer = new Buffer(content.length - 22);
        content.copy(newBuffer, 0, 22, content.length);

        // const sliced = content.slice(25);
        console.log(newBuffer);
        fs.writeFileSync('new.jpg', content);
....

I also made a small express application with one route to upload the image to S3 and I sent the image from Android in the same way and it worked, I could open the image. Is there anyone having the same/similar issue?