She said she planned an article similar to The Sunday Times's 'Best Companies to Work For' annual survey, but based on PR agencies.
C&W told PRWeek she only provided a mobile phone number.
PRWeek's repeated calls to the mobile have been transferred to the voicemail of a woman with a different name. Messages have not been returned.
The Sun said it had heard of neither Amanda Jones nor the name on the voicemail.
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