I am using the mandrill api to automate some tasks for domain creation and verification using nodejs. Below is the part of my code that is having issue.

    const sendingDomainCommand = mandrill_client.senders.addDomain({domain: domain.join(".")}); // adding a domain in mandrill
    await sleep(10000)
    const sendingDomainResult = await sendingDomainCommand;
    console.log(sendingDomainCommand);

According to below mandrill/transactional api the senders/add-domain should return a json response. https://mailchimp.com/developer/transactional/api/senders/add-sender-domain/

But in my case when I am printing the sendingDomainCommand it always shows null. I used the typeof to check the the type of this and it is object. can someone help me here please?