DataProvider in TestNG with Builder pattern returns Data provider mismatch (Rest Assured)

I tried to implement builder pattern into my code and I'm stuck with DataProvider. When I'm tring launch test I get an error:

org.testng.internal.reflect.MethodMatcherException: 
[public void api.tests.DpTests.msgCenterCase(testdata.dataprovider.Dataprovider2)] has no parameters defined but was found to be using a data provider (either explicitly specified or inherited from class level annotation).
Data provider mismatch
Method: msgCenterCase([testdata.dataprovider.Dataprovider2 arg0])
Arguments: [(testdata.Dataprovider2TestData$Dataprovider2TestDataBuilder) Dataprovider2TestData.Dataprovider2TestDataBuilder(createHeader=String, updateHeader=String, createDP=DataProviderObject(field1=field, field2=field, field3=field, field4=field), updateDP=null)]

    at org.testng.internal.reflect.DataProviderMethodMatcher.getConformingArguments(DataProviderMethodMatcher.java:46)
    at org.testng.internal.Parameters.injectParameters(Parameters.java:909)
    at org.testng.internal.invokers.MethodRunner.runInSequence(MethodRunner.java:37)
    at org.testng.internal.invokers.TestInvoker$MethodInvocationAgent.invoke(TestInvoker.java:969)
    at org.testng.internal.invokers.TestInvoker.invokeTestMethods(TestInvoker.java:194)
    at org.testng.internal.invokers.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:148)
    at org.testng.internal.invokers.TestMethodWorker.run(TestMethodWorker.java:128)
    at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
    at org.testng.TestRunner.privateRun(TestRunner.java:829)
    at org.testng.TestRunner.run(TestRunner.java:602)
    at org.testng.SuiteRunner.runTest(SuiteRunner.java:437)
    at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:431)
    at org.testng.SuiteRunner.privateRun(SuiteRunner.java:391)
    at org.testng.SuiteRunner.run(SuiteRunner.java:330)
    at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:52)
    at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:95)
    at org.testng.TestNG.runSuitesSequentially(TestNG.java:1256)
    at org.testng.TestNG.runSuitesLocally(TestNG.java:1176)
    at org.testng.TestNG.runSuites(TestNG.java:1099)
    at org.testng.TestNG.run(TestNG.java:1067)
    at com.intellij.rt.testng.IDEARemoteTestNG.run(IDEARemoteTestNG.java:66)
    at com.intellij.rt.testng.RemoteTestNGStarter.main(RemoteTestNGStarter.java:109)


Test ignored.

I can't see what's the problem because in builder class I am building whole object and pass it to method as argument.

Test class:

package api.tests;

import client.ApiRequestModel;
import org.testng.annotations.Test;
import testdata.Dataprovider2TestData;
import testdata.dataprovider.Dataprovider2;

public class DpTests {
    private Dataprovider2TestData createDP;


    @Test(dataProvider = "dataproviderTest", dataProviderClass = Dataprovider2.class)
    public void msgCenterCase(Dataprovider2 dataprovider) {

        ApiRequestModel DPRequest = ApiRequestModel.builder()
                .endpoint("/DPEndpoint")
                .body(createDP.getCreateDP())
                .build();


    }

}

DataProvider class

package testdata.dataprovider;

import model.fulfillment.DataProviderObject;
import org.testng.annotations.DataProvider;
import testdata.Dataprovider2TestData;

public class Dataprovider2 {

    @DataProvider(name = "dataproviderTest")
    public static Object[][] headerVersions() {
        return new Object[][]{
                {
                        Dataprovider2TestData.builder()
                                .createHeader("String")
                                .updateHeader("String")
                                .createDP(
                                DataProviderObject.builder()
                                        .field1("field")
                                        .field2("field")
                                        .field3("field")
                                        .field4("field")
                                        .build())

                }
        };
    }
};

Data provider Test Data class

package testdata;


import lombok.Builder;
import lombok.Data;
import model.fulfillment.DataProviderObject;

@Data
@Builder
public class Dataprovider2TestData {

    private String createHeader;
    private String updateHeader;
    private DataProviderObject createDP;
    private DataProviderObject updateDP;

}

Data Provider object class

package model.dp
import lombok.Builder;
import lombok.Data;

@Data
@Builder
public class DataProviderObject {
        private String field1;
        private String field2;
        private String field3;
        private String field4;

    }

I was trying make data provider as non-static and some combination with data. Everything works fine when I use simple Strings in DataProvider but with object it doesn't.

Your data provider method dataproviderTest is returning an array of arrays, where each inner array contains a single object of type Dataprovider2TestData. But, the test method msgCenterCase expects a single argument of type Dataprovider2.

You need to change the data provider method to return an array of Dataprovider2 objects. Modify the data provider method as below :

@DataProvider(name = "dataproviderTest")
public static Object[][] headerVersions() {
    return new Object[][]{
            {
                    Dataprovider2.builder()
                            .createHeader("String")
                            .updateHeader("String")
                            .createDP(
                                    DataProviderObject.builder()
                                            .field1("field")
                                            .field2("field")
                                            .field3("field")
                                            .field4("field")
                                            .build())
                            .build()
            }
    };
}