Error "unable to find valid certification path to requested target", when creating a request using OkHttpClient


I am trying to attach a text document to soap request. Based on some of the online responses, I was able to put the following code together but unfortunately this doesn’t work and throws the following

"unable to find valid certification path to requested target "

I can run my other requests where I don’t need to build the request like this, so what is it in this code that cannot read the certification defined under settings?

Thanks, any help will be appreciated

OkHttpClient client = new OkHttpClient().newBuilder().build();
String filePath = RunConfiguration.getProjectDir() + "/MyFile.txt"
File file = new File(filePath);

//Form request body that will be a multipart
 RequestBody requestBody = new MultipartBody.Builder().setType(MultipartBody.FORM)
	.addFormDataPart('UserId', "AAA")
	.addFormDataPart("file", file.getName(),  
 RequestBody.create(MediaType.parse("application/text"), file))

  //Form the actual request adding necessary headers
  Request request = new Request.Builder()
	.addHeader("Authorization", "Basic adfkskskdfkshfkjhsdafj")
	.addHeader("Content-Type", "charset=UTF-8;")
	.addHeader("Accept", "*/*")

Response response = null;

	try {
		response = client.newCall(request).execute();
		println("************ IMPORT TEST EXECUTION RESULTS RAW RESPONSE ************");
		println("Response status: " + response);
		if (response.isSuccessful()){
			String responseBody = response.body().string();
			println("************ IMPORT TEST EXECUTION RESULTS RESPONSE BODY ************");
		} else {
			throw new IOException("Unexpected HTTP code " + response);
	} catch (IOException e) {