Usage incorrectly charged

[Laura]

Hi

In November I signed up with Plus.net for a 1GB package per month, if I exceed this amount they don't charge me anymore, but slow my speed right down.
Over the last couple of months I have easily stayed within the 1GB, however this week I have been told I have already exceeded my monthly usage in the first week. I checked out the usage on their website and I have been charged for usage this week for days when I wasn't at home and overnight when I never leave my computer on etc etc.
I have a BT voyager 210 which in not wireless, I always switch it off when I turn the computer off and unplug it. I was actually away on Tuesday and Wednesday of last week but they tell me that i was connected at 5pm on Wednesday when I wasn't even here - router was unplugged as usual and there is no one else in the house.
Please can anyone offer any advice, as to date I am not getting anywhere with plus.net and the speed is frustratingly slow.
Thank you very much
Laura

Are you sure no one is connecting to a wireless connection and stealing your bandwidth?

[Laura]

Hi

I don't have wireless, but PLusnet have looked into this for me and it seems that another person is logged in as well as me - so they have got my password from somewhere.Very annoying!
Thank you for your help
Laura