I would call Hardie, it looks like they are not telling the truth and used third party paint. Rapid fading and chalk like texture is a dead give away. Hardie put out a document called Touch-Up Notice to Contractors and Consumers, here is what they say. initial color match of paint to ColorPlus products may not be as good as JH Touch-up match to JH ColorPlus products. Paint may age more rapidly from outdoor exposure than JH Touch-up and ColorPlus products. Paint may change color and chalk more rapidly than ColorPlus products in outdoor climates due to UV and moisture. Thee touch up paint is specially formulated and has gone through rigorous weathering testing against third party products to limited aggressive fading and stays in line with the color plus. Also where the hardy meets that trim should be caulked but it does not look like it. Is a lot of the caulking around everything white or did they use color plus caulk? More on reddit.com

I have reluctantly had to paint Hardie Color plus. The builder installed Hardie and the installer smeared caulk all over the boards and put it too thin in the joints with the trim. The caulk was deep ocean blue and the sun faded the blue caulk to nice pink. Instead of scraping all the link caulk (literally everywhere) it was easier to just paint the whole house. I believe they used Benjamin Moore Superpaint. It’s been 5 years since it’s been painted and we have had no issues whatsoever ever. We are on a hill facing the south and even the south facing side which gets beat by the sun has not seen an noticeable wear yet. More on reddit.com

Buy it primed and paint it whatever color you want. More on reddit.com

Best bet is to bring in a piece of siding and have them color match it. Any paint store can do this. I also found this quick writeup. More on reddit.com