I am looking to go to HAV in November. Google flight tells me that its possible to fly GLA-LGW-MAD-HAV, but BA wont show me a fare. Iberia shows me a fare from LON-HAV only, and nothing when I add Glasgow to this. lastminute.com sells me all of the flights.

Do I have to phone BA for a fare, or is there a hack to do this? If I phone up and add one days hotel stay at the start and end of the holiday can I have it as a BA holiday and book it with a deposit and pay the balance before I travel?

I thank you in advance for your help.