Matrix cheated me during UK and UK island visit

On 3rd December I got a matrix Sim from Delhi international Airport.
The Matrix agent told me that I will be having incoming free as long as I am in UK . I asked them whether it will be free for jersey (a UK Island) they said it is part of UK so it will be free and no roaming charges will apply.
I was commuincated that i can call 30 minutes daily limit free from UK back to India.

On Reaching my destination in Jersey (UK island), I made calls back to india well within free limits of 30 minutes.
and it was going on.
Suddenly yesterday I got messages from Matrix that My bill has reached to 4000.
i was wondering , I had not made any call other thatn free limit how it became Rs4000.
I immediatley swithced off my mobile and today when I switched on my mobile I saw one sms that my bill has reached up to 4500.

I wonder even without using in switch off state how it got increased to Rs4500 from the so called bill of Rs 4000.

I have mailed this to their customer care.
I donot hope any good from the frauds and I feel cheated really.

I will never recommend any one to but sim from such a fraud company.

Cheated...Alas.