ORANGE CITY, Fla. – When Nick Robin arrived to open up his auto repair shop early one morning last month, the phone was already ringing.
As soon as he answered the call, another one came in -- then another, and another.
"We didn't know what was going on at first. The calls were rolling in as fast as we could take them," said Robin. "It was lighting up the lines back to back."
Days later, calls continued to pour in to the Orange City business.
"Probably thousands," said Robin, who received calls from nearly every part of the country. "I actually erased about 500 voicemails yesterday."
The people contacting Masters Auto Centers were not Robin's customers trying to schedule a tuneup or repair.
Instead, they were recipients of an automated telemarketing phone call, commonly known as a robocall, that was advertising a potentially fraudulent health insurance product.
"They will start screaming at me saying, 'Stop calling me!' Or, 'Take me off your calling list!' And of course there are a few choice words in there," said Robin.
As the business owner soon discovered, telemarketers had hijacked his company's phone number in a practice called "spoofing."
Whenever recipients received the robocall, the phone number for Robin's Orange City business appeared in their phone's caller ID. If they attempted to redial the number, the callers were connected to Masters Auto Centers instead of the telemarketer.
"It's driving us crazy," said Robin, who eventually disconnected a telephone speaker in his auto repair garage because the sound was distracting his mechanics. "It was just one constant ring the whole day."
Worse than the annoying bells and chimes, the onslaught of unwanted calls has prevented Robin's customers from being able to contact the business.
"I've talked to two customers today when we normally would have 20 or 30 people that we talk to in a day," said Robin. "There's been no scheduling happening. Today is pretty much a loss. Tomorrow is going to be a loss. It's going to hurt us bad."
According to the Federal Communications Commission, it is illegal to spoof phone numbers if the caller transmits misleading or inaccurate caller ID information with the intent to defraud, cause harm or wrongly obtain anything of value.
In May, the FCC issued a $120 million fine to a Miami-based telemarketer who was accused of using spoofed phone numbers in a major robocall operation.
The FCC is working on a system that would authenticate caller ID information to ensure calls are coming from the phone numbers they claim to be.
Until such measures are implemented, government regulators acknowledge there is not much consumers can do to prevent their phone numbers from being hijacked by telemarketers.
Victims of telephone spoofing can file complaints with the FCC and the Federal Trade Commission to help investigators identify large-scale telemarketing operations.
Another way to minimize problems caused by spoofed phone numbers is to download third-party mobile apps that identify and block fraudulent phone numbers.
"Ninety percent of these robocallers are changing their number every single day. At upwards they'll use a number up to a few weeks," said Aaron Foss, the founder of the telemarketer-blocking app Nomorobo.
Nomorobo has flagged the phone number for Masters Auto Centers as being a potential health insurance scam and is warning app users not to answer calls from that phone number.
"While the attack is going on, that number is on our blacklist and we're protecting people from getting those robocalls," said Foss.
As a result of those calls being blocked, the telemarketers will likely be forced to abandon the phone number for the auto repair shop and select a new number.
"It gets shut down, the calls can't get out and they can't make their scams work. So they're just going to keep on changing their numbers," said Foss.
About a month after Robin first discovered his company's phone number had been spoofed, the number of unwanted calls to his business had declined. The phone no longer rings incessantly.
But Masters Auto Centers continues to receive several calls every day from people who have received a robocall.
"It's scary to think that after all of these years of building a reputation with customers using this phone number that it can be taken in an instant and cause us a huge headache and a major financial loss," said Robin. "Is this going to happen again?"
Foss has advice for people who receive telemarketing calls from a spoofed phone number.
“Don't yell at the person on the other end. You're probably just making the problem worse. They're just as big of a victim as you are,” he said.