Budget airlines absolutely DETEST 'fare scraper' sites, such as SkyScanner, and do their absolute best to ensure that their fares don't appear on such sites. (Budget airlines make far more money from selling add-on, such as insurance, car hire and accommodation, than they do from many flights. So they need people travelling with them to have such offers leaping out at them when they book on their own websites, rather than not seeing them when they book through third parties).
So, while SkyScanner can be useful for long-haul flights, I'd never use it for short-haul ones. You can fly from Newcastle to Lanzarote for a total of £1078.20 for TWO people with Jet2, travelling out on either the 21st or 23rd December and returning on the 29th.
https://i.postimg.cc/q7zKkHdj/Jet2.jpg