A 10-year-old girl racked up a £1,792 bill on her mobile phone after watching videos on how to make loom bands.
Trinity Groves built up the massive charge over a two week period on her Nokia Lumia after her home's Wi-Fi stopped working.
Her dad Philip, 35, wasn't aware she'd been using Vodafone's premium service to watch 28 hours worth of online tutorials on how to make loom band designs on YouTube.
So he was stunned when his September bill landed on the doorstep of his home in Shrewsbury, Shropshire, to see he'd been charged £1,411.
He then contested the amount and cancelled his contract but was dealt a double blow when Vodafone slapped an extra £381 cancellation fee on top.
Philip has criticised the phone network for the extortionate fee without any prior warning.
He told his local paper: "We thought we were using the Wi-Fi for a good fortnight and there was nothing to suggest it had disconnected.
"I wasn't informed otherwise. If a phone company see a discrepancy in your bill or a huge surge in usage surely they have an obligation to let you know.
"Now they are threatening to take me to court - it's frightening that they can bully you this way."
Trinity said she had been left feeling 'very sad' after learning she had ran up the bill watching clips about loom bands.
She added: "I like to watch the YouTube videos on my phone, they teach me new techniques and different ways of doing the bands.
"I spent a lot of time watching the videos because they are long and I have to pause them often.
"I used to love watching the tutorial videos but now I know it cost my dad £1,792 I have had to stop watching them - it's made me very sad."
Vodafone hasn't commented on the case.
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