Been charged for additional broadband usage & don'...

Question

I have 2 broadband connections into my house. One is a BT infinity line with 40gb included & The other is an unlimited business line through another company.
We've had the infinity line for just over a year & originally the only devices connected to it were the BT Vision box, my sons ipad & my sons iphone. Mine and my husbands devices are all connected to the business broadband. We connected my sons to BT as a way of monitoring his usage but he's only 9 so we weren't anticipating huge usagev through it. Since Christmas my parents smart phones have been connected to it but they are only in our house for 2 hours every 2 weeks or so and as they are in their late 70's they're not playing games or downloading on them
On January 13th I had an email saying I was at 28gb and then on the 19th one to say i was at 36gb. I didn't think too much about it. Then on 18th Feb I had an email to say I'd used 72gb in January. I should probably have looked into it more closely at the time but I've been battling cancer so it really didn't rate high on my priorities at the time. However when I got an email on 12th April saying usage for the April was already at 28gb I told my husband to disconnect my sons devices from the BT Internet and connect them to our unlimited broadband. Despite him doing thisI got another email on 14th April saying we were at 36gb and then yesterday I got an email to say we had used 58gb in April. Struggling to understand how we can have used 22gb with no devices connected to it apart from the BT vision box and maybe one or two phones for a handful of hours.
I've spent 2 hours on live chat tonight with a very nice person in what I presume was India from his name & he sent me a day by day breakdown of my usage for the past 30 days. Interestingly it showed 3.5 gb of usage on a day that my son and I were staying in a hotel & my husband was out at work all day. This also shows usage this month so far of over 16gb with virtually nothing other than BT vision connected to it all month. The gentleman on livechat suggested someone else might be using our broadband but I'm not sure how this can happen. Other than that he couldn't suggest anything to help me resolve this issue. I am obviously disputing the additional charges I have incurred.
Can anyone help me as I'm at a total loss what to do next

Answer 1

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