I used dialtosave to call a landline abroad, instead of charging me the 1.5p rate advertised, they charged me at the 13p mobile rate.
They don't have a service line, or indeed any phone number (they are a phone company - you work it out), you have to use an automated, and complicated web system to complain.
When I put a complaint in they just stonewalled, I had to threaten them with the small claims court and solicitors costs to get my money back.
I strongly suggest you have nothing to do with them.
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