createBulkWriteJob-method not working in Node.js SDK V5.0

Hi,
I am trying to create a bulk write job using the new version of the SDK.
I am getting an error that says: unable to process your request. please verify whether you have entered proper method name, parameter and parameter values.
I have been using the method in the 2.0 version for 1.5 years and it has been working well, but something in the new version seems to be causing this error.
My code looks like this:
import * as ZOHOCRMSDK from "@zohocrm/nodejs-sdk-5.0"; 

export default class HoursBulkCreate{
    /**
     *  Create BulkWrite Job
     * This method is used to create bulk write job with the uploaded file ID
     * @param {String} moduleAPIName The API Name of the module.
     * @param {String} fileId The ID of the uploaded file to create BulkWrite Job.
     */
    static async createBulkWriteJob(moduleAPIName, fileId){
        
        //Get instance of BulkWriteOperations Class
        let bulkWriteOperations = new ZOHOCRMSDK.BulkWrite.BulkWriteOperations();

        //Get instance of RequestWrapper Class that will contain the request body
        let requestWrapper = new ZOHOCRMSDK.BulkWrite.RequestWrapper();

        //Set the charset of the uploaded file
        requestWrapper.setCharacterEncoding("UTF-8");

        //To set the type of operation you want to perform on the bulk write job.
        requestWrapper.setOperation(new ZOHOCRMSDK.Choice("insert"));

        let resources = [];

        //Get instance of Resource Class
        let resource = new ZOHOCRMSDK.BulkWrite.Resource();

        // To set the type of module that you want to import. The value is data.
        resource.setType(new ZOHOCRMSDK.Choice("data"));

        //To set API name of the module that you select for bulk write job.
        let minifiedModuleRecord = new ZOHOCRMSDK.Modules.MinifiedModule()
        minifiedModuleRecord.setModule(moduleAPIName)
        resource.setModule(minifiedModuleRecord);
        

        //To set the fileId obtained from file upload API.
        resource.setFileId(fileId);

        //True - Ignores the empty values.The default value is false.
        resource.setIgnoreEmpty(true);

        // To set a field as a unique field or ID of a record.
        // resource.setFindBy("Email");

        let fieldMappings = [];

        //Get instance of FieldMapping Class
        let fieldMapping = new ZOHOCRMSDK.BulkWrite.FieldMapping();
        resource.setFindBy("id");

        //To set API name of the field present in Zoho module object that you want to import.
        fieldMapping.setAPIName("Projekti");

        //To set the column index of the field you want to map to the CRM field.
        fieldMapping.setIndex(0);

        fieldMappings.push(fieldMapping);

        fieldMapping = new ZOHOCRMSDK.BulkWrite.FieldMapping();

        fieldMapping.setAPIName("Teht_v");

        fieldMapping.setIndex(1);

        fieldMappings.push(fieldMapping);

        fieldMapping = new ZOHOCRMSDK.BulkWrite.FieldMapping();

        fieldMapping.setAPIName("Ty_ntekij");

        fieldMapping.setIndex(2);
        
        fieldMappings.push(fieldMapping);

        fieldMapping = new ZOHOCRMSDK.BulkWrite.FieldMapping();

        fieldMapping.setAPIName("Tunnit");

        fieldMapping.setIndex(3);

        fieldMappings.push(fieldMapping);

        fieldMapping = new ZOHOCRMSDK.BulkWrite.FieldMapping();

        fieldMapping.setAPIName("PVM");

        fieldMapping.setIndex(4);

        fieldMappings.push(fieldMapping);

        fieldMapping = new ZOHOCRMSDK.BulkWrite.FieldMapping();

        fieldMapping.setAPIName("Owner");

        fieldMapping.setIndex(5);

        fieldMappings.push(fieldMapping);

        fieldMapping = new ZOHOCRMSDK.BulkWrite.FieldMapping();

        fieldMapping.setFindBy("id")

        fieldMapping.setAPIName("Projekti_Zohossa");

        fieldMapping.setIndex(6);

        fieldMappings.push(fieldMapping);

        resource.setFieldMappings(fieldMappings);

        resources.push(resource);

        //Set the array of resources to RequestWrapper instance
        requestWrapper.setResource(resources);

        //Call createBulkWriteJob method that takes RequestWrapper instance as parameter
        let response = await bulkWriteOperations.createBulkWriteJob(requestWrapper);

        if(response != null){
            console.log(response)
            //Get the status code from response
            console.log("Status Code: " + response.getStatusCode());

            //Get object from response
            let responseObject = response.getObject();

            if(responseObject != null){

                //Check if the request is successful
                if(responseObject instanceof ZOHOCRMSDK.BulkWrite.SuccessResponse){

                    //Get the Status
                    console.log("Status: " + responseObject.getStatus().getValue());

                    //Get the Code
                    console.log("Code: " + responseObject.getCode().getValue());

                    console.log("Details");

                    let details = responseObject.getDetails();

                    //Get the details map
                    if(details != null){
                        Array.from(details.keys()).forEach(key => {
                            console.log(key + ": " + details.get(key));  
                        });
                    }

                    //Get the Message
                    console.log("Message: " + responseObject.getMessage().getValue());
                }
                //Check if the request returned an exception
                else if(responseObject instanceof ZOHOCRMSDK.BulkWrite.APIException){

                    //Get the Status
                    console.log("Status: " + responseObject.getStatus().getValue());

                    //Get the Code
                    console.log("Code: " + responseObject.getCode().getValue());

                    console.log("Details");

                    //Get the details map
                    let details = responseObject.getDetails();

                    if(details != null){
                        Array.from(details.keys()).forEach(key => {
                            console.log(key + ": " + details.get(key));  
                        });
                    }

                    //Get the Message
                    console.log("Message: " + responseObject.getMessage().getValue());
                } 
            }
        }
    }
}