Existing customer deal - Disney plus hidden in the small print

Have been offered 1gig broadband for £3 extra a month on my current package via an email offer.  When I click through to sign-up and review the contract summary, Disney has been miraculously added, but is not mentioned anywhere else.  I don’t even know what it costs.  How do I accept this deal without the ‘secret’ add on? Apologies for posting here but that was the recommendation of Virgin’s customer service department who clearly weren’t willing to help.