You have two problems. First, your dog gets loose. Second, she won't come when you call her.
Let's address the first problem. If your dog keeps getting loose, you must solve this because it's dangerous for your dog. Running loose exposes her to all kinds of hazards: stray dogs, cars, etc. So if she is getting out of a fenced area, you need to fix whatever it is that is allowing her to get loose. Fix holes in fences, get a padlock for the gate, or keep her inside. Never take your dog out without a leash.
Second, you need to teach your dog to come in planned lessons. Take a look at Teaching Come. Practice a couple of times every day and making coming to you really fun. NEVER yell at or punish your dog when she gets loose and you finally catch her. She will never want to come to you then. Always make coming to you the best place in the world and she will happy to return to you. Use her favorite treats and lots of praise.