The experience of contacting Virgin about Mobile Broadband (which I don't seem to get at the advertised 20% off)

I'm having some trouble contacting Virgin. When I email them I get a response which is 99% standard text, with perhaps an extra sentence if I'm lucky. Each time they tell me to log in and fill out a 'contact us' form. When I try this, their website script falls over, as you can see in the picture below. When I tell Virgin about this by email they apologise that 'I am having trouble getting online' ask me to try again or phone them (for 10p). I keep trying and keep getting the same response. Now my only option is to make time during the working day and pay the requisite 10p to ask then why I am not getting my 20% discount. Not the best user experience I can imagine. Perhaps I should stop paying my bills and ask them for 10p to phone me about it!