What is the best approach for increasing FTP for zone 2, endurance, non-race rider?

Thanks mate. I typically do my own plans of primarily zone 2 & try to stick to it. It’s when I get to perhaps 4-6 weeks in that I see big declines with the gains being wiped out. I think I just need to get a better balance of being type 1 & doing the Training.

I did the ramp tests weekly so that as I improved I adjusted my wattage so my zones stayed accurate. I also though that doing them more regularly would help me get used to the toughness of the efforts. I see what everyone is saying though.