Sorry. Gonna have to disagree with you here as far as the bulbs themselves go. I have many LIFX minis and BR30s. Outside of a little bit of being finnicky when initially getting these tied to the network with their pairing process consisting of the bulb needing to join the bulbs own wifi channel initially, these bulbs are solid. I suspect this more than likely to be your issue since you could only get 3 out of 15 working. Unless of course you bought 15 and FedEx dropped your package from the sky and broke them all. The bulbs are so solid that I haven’t had to ever use support.
If I was Support, I would be confused by this example anyway.
I’m up to 16 A19’s. Occasionally I get a dropped bulb from the lifx cloud. A simple power cycle fixes that. I’ve found that assigning each bulb a static iP address helps.