The breeder I got Roxy from free fed her, but I wanted her on more of a routine and I wanted to control how much she was eating. I too fed her 3 times per day. Once in the morning, once in the afternoon, once in the evening. I still feed her 3 times a day. She's 10 months now. Some people feed twice a day. Totally fine too, you just give more to eat at one time the less times you feed. I like feeding 3 times a day though so that she doesn't have to wait for hours to eat. I never want to take the chance of her sugar dropping.
From personal experience, sometimes Roxy isn't hungry right away when I feed her. She LOVES her food and is always excited to eat, but there are days where she may have had a few extra treats or I fed her a little too early or whatever the reason, but she doesn't ALWAYS eat right away. She doesn't always eat it all at one time either. She may eat some, and then get distracted, and come back and eat the rest a little later. So, if I only put her food down and let her eat for 15 minutes and took it away, she wouldn't always eat her whole meal.
So, I think it just comes with trial and error and observing your dog and getting to know what they do. Maybe you're feeding too much with each feeding. I am not sure. A healthy dog won't starve them self though!
ALSO -- if you WOULD rather free feed, this is another option. When I'm at my apartment during the school year, I don't have to worry about other dogs eating Roxy's food. But now that it's summer and I'm home from college, I'm at my parents. We have two labs here. They always scarf up Roxy's food when they get the chance. So, we put a baby gate up and block off one room so Roxy can eat her food in peace and not have to worry about anyone else eating her food.