I recently upgraded my 'phone as I do every year or so and the nice lady told me that I was on the wrong contract. I could save a lot of money by switching to their Flext20. I explained what I used the 'phone for (texts, any network at no particular time and occasional internet access) and she confirmed that the Flext20 was the one for me.
The first few bills saw a massive saving but this month the bill was £190 (usually about £25)!!!
As I have been away from home for a week, I was using the moby to check my e-mails. Once in the morning and once at night for about 10mins each time (it took a long time as the 'phone
kept disconnecting itself.
£160 worth of internet use!!!
I 'phoned T-Mobile to ask if that was the cheapest way to use the tweb with them and they said that there were far cheaper contracts but they were substantially more per month if I wasn't using the tinterweb.
Lesson learnt! Don't play tinterwebnet from a T-Mobile 'phone!!!

Rant over......

Im on flext 20 too, only once used allmy allowance, but i added web and walk for an extra £7,50 which gives me unlimited access to web and emails,

ring them back and give them some stick

HTH
Mitch

Yep, I am on a FlexT package with the £7.50 a month webnwalk add-on. Unlimited data usage, bargain, far far cheaper than the other networks.

I left T mobile last week as there internet access via mobile was knobbled on my mobile.

I went to 3, good coverage round here, When I down in Cornwall the T Mobile phone didn't have coverage, the 3 phone still carried on and occasionally jumped to O2 where there was no direct 3 coverage.

yep sounds like you're on the flex option but WITHOUT web and walk. for mobile tinterweb there is no comparison, 7.50 a month for basically unlimited access, or i think 10 if you want to use it with your laptop too.

if they told you you were getting web and walk and you used internet based on that understanding then i'd be complaining.

unless of course you were roaming (abroad)? in which case the internet gets very expensive because it's not covered in web-n-walk obviously.

my phone collects my emails automagically every 30 minutes and i have to remember to disable this if i go abroad, or big bills face on my return!