Andersen doors have loose latches

Andersen doors (2579771-3P / 2579774-5P)

I have two doors that seem to have a broken internal spring (but I'm guessing at that). To shut the door I have to pull down on the latch until door is situated in the jamb, then pull up to engage all the points, and THEN gently release the latch so that it doesn't fall down. Totally doable and am used to it, but guests simply cannot figure it out, even ones with higher degrees. I'm guessing that the spring is a $1 part but that I'll need to buy a "400 Series Hinged Patio Door Active Lock Mechanism" that costs over $300. Wondering whether new doors would be cheaper. Thanks for any suggestions on how to proceed.