UNEXPECTED FEES. Faulty merchandise. Promises of service that fall short.

These things happen. And so does subpar service when you try to get matters fixed. Companies’ growing use of automation to handle customer support makes it especially challenging and confusing for consumers who need to reach actual human beings to get legitimate complaints resolved.

But do not fret! If you have a complaint about a cellphone provider, auto dealership, airline or other merchant, you can use this handy guide to get refunds and other forms of satisfaction.

→ Be AI-savvy. Increasingly, companies are ceding their customer service operations to AI-driven chatbots, both online and over the phone. If you’re getting no help from robotic replies in a call or online chat, using these phrases may help you reach a real person: “representative,” “customer service,” “speak to human,” “talk to professional,” “live support,” “supervisor,” “complaint,” “account issue” or “escalate.”

→ Be polite. If you reach a human being, that person usually isn’t the one who caused your problem. “For the benefit of your own soul, remind yourself that there’s another human being at the other end of the phone line,” says consumer affairs journalist Bob Sullivan, who hosts AARP’s The Perfect Scam podcast. “This is a person who might have a choice to either benefit you or not benefit you.”

→ Be clear. Be upfront about what you expect to get. “Don’t just be mad,” Sullivan advises. “Have a resolution in mind. Say things like ‘You charged me this fee. I don’t deserve to pay it. I should be refunded this amount.’ ”

→ Use your time wisely. Make sure the end goal is worth it before you begin—for example, that you’re willing to spend three hours to claw back a $10 overcharge. And early on, ask representatives you’re speaking to whether they have the authority to give you what you want. If not, say you want to talk to the person who does, Sullivan says: “This way, you’re not wasting your time.”

→ Document, document, document. Keep a record of all interactions (and attempts to interact) with the merchant. That might include notes of phone conversations, such as the date, time, person spoken to and promises made; screenshots of online chats; and copies of emails sent and received. Should your problem escalate, having all this material on hand can help support your case with company higher-ups, regulators and other government officials.

→ Be quick. Whenever possible, speak up about your concerns in person. By addressing the issue in real time while you’re still on vacation or on the car lot, you give the business more options for fixing it. If your complaint involves calling or emailing a company after you’ve noticed a problem, give the other party no more than a week to 10 days to resolve it before escalating the issue, advises Teresa Murray, Consumer Watchdog director for the Public Interest Research Group. “As time drags on, you lose some of your rights,” she says. “Do it while the details are fresh.”

→ Climb the company ladder. Christopher Elliott, a journalist and consumer advocate, maintains a list (at elliott.org/company-contacts) of customer service emails and phone numbers for scores of national companies. If those don’t get you satisfaction, he also has contact info for key executives at many of those companies. Keep emails brief, polite and factual, he advises.

If you’re finding unexpected or confusing charges on your bill, start by reviewing your cellphone contract to check whether introductory offers have expired, Murray suggests. If you feel you have a valid complaint, contact the cellphone provider directly to ask for relief. If that doesn’t work, visit consumercomplaints.fcc.gov, where you can file a report with the Federal Communications Commission.

You’re entitled to a cash refund on domestic flights if, for any reason, your flight is canceled or delayed for more than three hours for your departure or arrival. If the problem is your carrier’s fault—say, its computer went down—you could be due a free meal for the delay. If you have to fly out the next day, you should get a free hotel stay. (If the delay is weather-related or otherwise outside the airline’s control, you’ll probably have to foot your own food and lodging.)

Visit transportation.gov/airconsumer and click on Flight Delays and Cancellations to find different airlines’ customer service commitments. With that information, approach your airline’s counter at the airport and politely ask about meal vouchers, hotel accommodations and ground transportation, as appropriate.

As soon as you spot a problem, reach out to someone at the hotel’s front desk or contact a vacation property's host, calmly describing the problem and your hoped-for resolution. If that doesn’t work and there’s no higher-up to appeal to, start working from the bottom up the next day: the local hotel management, then the chain’s corporate headquarters—or, if it’s a vacation rental, the vacation rental platform’s help center. You’ll typically need to complain about a vacation rental within 72 hours of discovering a problem, and you’ll be expected to document the problem as well.

In especially egregious cases, you can use what Elliott describes as the “nuclear option”: filing a dispute with your credit card company to get the charge for your stay reversed.

Complaints about contractors are so common that it’s always wise to hire contractors who are licensed, bonded and insured, Murray says. If speaking with the contractor doesn’t yield results, you can file a complaint with the city where you’ve (ideally) gotten a permit and, if your contractor has a state license, with your state.

Many states have funds with names like Homeowners’ Construction Recovery Fund or Residential Recovery Fund from which you might get financial relief, says Erin Witte, senior counsel on consumer protection for the New Jersey Office of the Attorney General. “That’s a situation where you should definitely file a complaint and have your documents in order,” she says.

Familiarize yourself with your state’s lemon law, covering problematic cars, advises Ronald Montoya, manager of consumer advice for the automotive site Edmunds.com. “As a general rule, the car needs to go into the shop for the same issue three times or it must be out of service more than 30 days to be considered a lemon,” he says. For persistent car problems, ask the following people for help in this order: the service adviser in the dealership’s service department, the service manager, the general manager of the dealership and—in extreme cases—the car brand’s corporate office.

You might also consult another dealer within the same brand to get a fresh set of eyes on the problem, Montoya says. If all this doesn’t help, you can file complaints with the state attorney general’s office; a city or county consumer affairs department; and a Motor Vehicle Dealer Board, an Auto Dealers Association or organization with a similar name that oversees dealerships in your state.