Contact GHD asap. That's how I knew something was off with my straightener. The first time it happened the same thing to me, I turned it off, removed from the plug and waited and tried to turn it on again but I still get the red light flashing on and off. I tried doing it for a few times but still had the same issue so I contacted GHD and they replaced my straightener but after a few months it happened again. It sucks because for the price we pay for these straighteners we expect quality but unfortunately it isn't the case with these products.
For me, the first and still very best of all ceramic stylers [and my dad is a hairdresser too]. It heats up fast, cools down relatively fast, works wonderfully and lasts a long time. In 11 years, I've bought two such stylers. The first one eventually died after 6 years of daily use, rarely skipping a day, while my second one is still going strong. I have no reason to recommend any other styler but this one. My hair is long and very fine.