Asked plusnet to change telephone billing to free UK calls anytime

[#1]

Hi I did this in January. Then my billing was not changed, I didn't check to see, rather stupidly you might think, anyway as it pans out they did not change my plan & have been billing me for daytime calls, which works out rather expensive. They say they have no record of the call what should I do, what can I do?

[#2]

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Hi I did this in January.

Hi there, can you tell us how you did that so I can check your account further?
The reason I ask is that 55346141 shows  this being requested on 10/5/12 and would be activated on 9/6/12.