plugins.http error PKIX path building failed

Hi,
I am trying to upload an xml to a web service to be validated. I have read the Servoy documentation for the http plugin but it always gives me the same error when execute the request.
“PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target”
I think it is a problem with the digital certificate that I want to use for sending. I have imported the digital certificate that I want to use for sending to the Java Keystore cacerts but it keeps giving me the same error.
This is the code that I have generated in Servoy and I would appreciate any help or explanation of why it gives me this error and how to solve it so that I can upload the xml to the web service correctly. Thanks.

function envioTBAI(myXml){
//myXml = path where I have the xml. Example "c:\tmp\TBAI2209713_firma.xml"
var url = "https://tbai-z.prep.gipuzkoa.eus/sarrerak/alta";
var client = plugins.http.createNewHttpClient(); // Creating new http client
var poster = client.createPostRequest(url);

poster.addHeader("Content-Type", "application/xml");
poster.addHeader('Accept', 'application/xml');
poster.setCharset('UTF-8');
	
poster.addFile(null,'XMLTBAI',myXml,'text/xml');

var response = poster.executeRequest()
var pageData = response.getResponseBody();
	
//Get Status Code. 200 is OK
application.output("Response status code: " + response.getStatusCode());
application.output("Response reason: " + response.getStatusReasonPhrase());
application.output("Response body: " + response.getResponseBody());
application.output("Response exception msg: " + response.getException());
	
response.close();
client.close();

return pageData
}

You should also import any root/intermediate certificates that are missing to your keystore.

The error sounds like something is missing in certificate chain.

You probably didn’t import the certificate into the right keystore.
For the developer you need to check in the servoy.ini file where -vm points to.

In case of 2022.03 rc1 (windows) it is plugins/com.servoy.eclipse.jre.win32.x86_64_17.0.2/jre/bin/server/jvm.dll
So you must import the certificate to that jre \developer\plugins\com.servoy.eclipse.jre.win32.x86_64_17.0.2\jre\lib\security