Every person who phoned 118 118 between October 1 and October 12 had the chance of winning £118.
However, when the 288 randomly selected winners where informed of their prize by phone, 89 refused to take the money due to suspicions of fraudulent spam and scam calls.
Now 118 118 has uploaded the winning names onto its website in the hope it can persuade the winners that the prize money is not a scam.
William Ostrom, spokesman for 118 118, said: "It was the strangest thing. We were calling people to give them money and they were refusing.
"In these credit crunched times we couldn't even give money away. It appears that people's wariness has been caused by experience of fraudulent calls, spam and 'too good to be true' offers with strings attached."
118 118 plans to repeat the competition next month but will be increasing the prize pool to £1,180,000