When does your puppy ignore you when you say "COME"?
I practice recall with my dog a lot. I even enrolled in the Recallers course (which I am very very behind on).
My dog has ignored my "COME" on a few occasions. Once, when she did not want to come inside from the backyard after peeing. I was so pissed
And while she was running around playing with another dog -- although she did come after I yelled very loudly and got her attention -- but only for a brief moment before running off again to chase the other dog. Once she burnt off the crazy energy, she came readily, and even maintained a sit, and got rewarded with some treats.