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I have only been a Vodafone customer for 9 days and while I know my speeds will vary during the first 10 days or so I do not expect the connection to be continously dropping, yesterday it happened over a dozen times before it was even 1pm.
I got in touch with live chat who did nothing but annoy me with irrelevent questions that got me absolutely nowhere, he said he would ensure this does not keep happening yet here I am again the very next morning with the exact same problem - and I can't even access my router settings using the IP adress as it locks me out every time I try to log in - which is a common issue judging from Google searches I have done on the subject.
I've also wasted a substational amount of my data allowance using live chat to get this sorted since I keep getting cut off when connected through my router.
As I say, 9 days into my contract and I'm already considering cancelling it - simply not good enough.
I had exactly the same symptoms (constant random line drops) It took 3 months to sort and in my case was a fault on the fibre. (I'm on Superfast 2 FTTC). I know that Vodafone have no direct control over the fibre and have to rely on Openreach but the hoops you need to jump through to get them to manage the problem is exhausting.