SharePoint 2016 500 (Internal Server Error) When uploading

Question

Hello Everyone, i am facing an issue with Sp16 when i upload many documents using rest API. when i upload many documents each one is 20mb i am receiving error 500 Internal server error.

any idea about this error and how to solve it?

i tried this https://www.vioreliftode.com/index.php/how-to-make-sharepoint-2016-not-fail-long-running-uploads-large-files/ but it didn't work for me. any other suggesstions?

my post request is below

public async Task<bool> Save(string requestUri, HttpContent content)
{
    var credential = new System.Net.NetworkCredential(
        username,
        password,
        domain);
    using (var handler = new HttpClientHandler() { Credentials = credential, UseProxy = false })
    {
        using (var client = new HttpClient(handler))
        {
            client.DefaultRequestHeaders.Accept.Clear();
            var mediaType = new MediaTypeWithQualityHeaderValue("application/json");
            mediaType.Parameters.Add(new NameValueHeaderValue("odata", "nometadata"));
            client.DefaultRequestHeaders.Accept.Add(mediaType);
            client.DefaultRequestHeaders.Add("X-RequestDigest", await this.GetRequestDigest());
            client.DefaultRequestHeaders.Add("binaryStringRequestBody", "true");
            string postUrl = this.siteUrl.EndsWith("/") ? $"{this.siteUrl}{requestUri}" : $"{this.siteUrl}/{requestUri}";
            this.logger.LogDebug("Executing SharePointService.Save: PostUrl={0}.", postUrl);
            HttpResponseMessage response = await client.PostAsync(postUrl, content);
            response.EnsureSuccessStatusCode();
            this.logger.LogDebug("Executed SharePointService.Save: PostUrl={0}", postUrl);
            return true;
        }
    }
}