plus net threat letter

I have been with Plus.net for about 3 weeks on their £14.99 premier account.
Up until today I have used 6.9Gb according to their online stats. Yet they
have sent me an email warning me that my usage exceeds the monthly
allowance.
What the heck is going on? Their website states the "clean allowance" is
20Gb a month. My usage this month will end up being less than 10Gb, it was
only even that much so far because I downloaded some linux isos. usually it
is far less.


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