John Arwe first noticed a suspicious charge on his Verizon phone bill last December and then two more charges in January.
"It's easy to miss. I mean you're talking about eight or maybe 15 bucks out of 150 a month," Arwe said.
The charges were from companies independent of Verizon who were listed on the bill as "other providers."
"Companies other than your phone company are allowed to put charges on your phone bill for things like voicemail service or a directory listing. The trouble is, charges you didn't authorize can be slipped on your bill," said Kim Kleman, editor-in-chief of Consumer Reports magazine. "It's called 'cramming,' and there are plenty of victims."
The Federal Trade Commission had more than 3,000 complaints of cramming last year.
"A big problem, with so many separate companies involved in the billing, is it's tough to get any of them to take responsibility for unauthorized charges," Kleman said.
Arwe spent more than 20 hours trying to get his money back. Finally, Verizon agreed to credit his account pending its investigation.
"You can protect yourself against cramming before it happens. Ask your phone company to put a 'cramming block' on your account. That will immediately stop other companies from placing charges on your bill," Kleman said.
And go over your bill as Arwe does with a fine-toothed comb, and if you spot an unauthorized charge, demand a refund from your phone company right away.
Consumer Reports says if you find you have unauthorized charges on your phone bill, besides calling the phone company and demanding a refund, report your complaint to the Federal Trade Commission.