Foolishly replied to text from Vodaphone offering free data. No charge mentioned but turns out I had agreed to an extra GB per month at an extra charge of £6 per month! Took hours to resolve and I was told initially that there was no extra charge and that it was a gift for a loyal customer! Idiot customer more likely as I could upgrade if I wished to the same package for £3.50 per month. Furious that this has happened - the marketing strategy is to trick customers into paying more. I have been loyal to Vodaphone for years but am now looking to move elsewhere.