When you rent a car, you’re probably focused on your trip, not whether you’ll be banned from renting. Yet many drivers end up on a car rental company’s dreaded “Do Not Rent” (DNR) list. Sometimes, it’s a billing misunderstanding that ultimately gets worked out. Other times, it’s something completely unexpected you might not ever feel “at peace” with.

Consumer advocate Michelle Couch-Friedman shared multiple DNR list cases on Fodor’s. Through her organization, Consumer Rescue, she helped several rental car customers understand the circumstances leading to their placement on a DNR list. Here’s how it happens and what you can do to stay off a rental car company’s blacklist.

They don’t like it when you file a credit card dispute

Disputing a charge on your credit card might seem like an easy way to resolve billing issues. In fact, Couch-Friedman says that rental car companies rarely even respond to banks regarding chargebacks. Instead, though, they just add customers to their DNR lists.

But for Jenny Lehman, it turned into a nightmare. She disputed a $500 charge with Enterprise, believing she was erroneously billed after a car accident. Her initial argument was that the at-fault driver’s insurance company sent Enterprise $500 already. Another $500 charge to her credit card, then, was totally uncalled for. Her bank sided with her, but Enterprise didn’t drop the matter. Instead, they sent her account to collections and banned her from renting at Enterprise, National, and Alamo.

Later, after contacting Couch-Friedman, Lehman realized Enterprise had actually forwarded the original $500 insurance payment to her through a separate check. She found a record of her cashing Enterprise’s check shortly after receiving it. In the end, Lehman was quite embarrassed to find Enterprise was correct in its $500 credit card charge. After paying back the disputed amount, her rental privileges were restored.

Always double-check your records and try to work directly with the rental company before escalating disputes.

Losing your cool during interactions with rental car company staff can get you banned

Emotions can run high during travel, but venting at a car rental counter could get you blacklisted. Oliver, a long-time Hertz customer, was banned after a heated exchange at check-in. Frustrated by a lack of available cars, he raised his voice and slammed his bag. Though he apologized, Hertz deemed his behavior unacceptable and made the ban permanent.

Car rental companies take employee safety seriously. If you’re stuck in a frustrating situation, take a deep breath and step away before things escalate.

Damage disputes leading to unpaid bills lands customers on DNR lists

Returning a rental without settling all charges can also get you banned. Susan Drury found this out when Hertz charged her $700 for a damaged rearview mirror after she returned a car. Drury believed the damage wasn’t her fault but hadn’t documented the car’s condition before driving off. Without proof, Hertz held her responsible.

To resolve the issue, she paid the bill and was reinstated. The takeaway? Always inspect and document your rental car thoroughly, and address any concerns before you leave the lot.

Car rental companies have little tolerance for disputes, damage, or disruptions. To avoid landing on the DNR list, communicate calmly, document thoroughly, and resolve issues promptly. It’s easier to prevent a ban than to undo one.