Macbook Air 2018 version, Keyboard keeps double spacing!

Does anyone else's Macbook Air (2018 version) keep double spacing? I bought this macbook in December 2018 so its about a year and 5 months old right now, although this started happening in February 2020. It's so annoying especially when I have to write an essay for school!! Its been over a year so what can I possibly do? Does anyone know why this is happening? And do I have to pay to get it fixed or is there anyway apple could help me with it for free as its only been a year and a bit and normally laptops should last longer. I haven't been mistreating my laptop, i'm very careful with it.