Don't feed her anything else until she eats it. My corgi wouldn't eat his dry food until I started giving him a treat immediately after he finished. If he wouldn't eat, I would say "treat" several times and point to his bowl. He ate the food, and recieved a treat. He eventually got it down, it just takes several tries :)
Your puppy has you trained to given her only wet food. Just stop giving her the canned stuff (which isn't good for her teeth and is more expensive); when she's hungry, she'll eat the dry food. My two dogs get excited about breakfast & supper every single time, and it's the same dry kibble every single time. They get canned food as a big treat only a couple of times a year.
What else are you feeding her? Never give dogs "people food," many things people eat can be harmful to dogs. I've always fed all my dogs dry dog food, twice a day, never any people food. Dry food is like a toothbrush for dogs, helps clean their teeth, and good brands have all the nutrients a dog needs for overall good health. I don't like to give dogs canned food; it's mushy & does nothing to help clean their teeth, plus... it tends to give them stinky gas & diarrhea... that's never fun. If you're feeding your shepherd canned food -- stop -- give her dry food only. When she has nothing but dry food to eat, that's what she'll eat. Don't feel bad, it's not cruel & the dry food is healthier for her. She'll get used to it & you can give her a dog treat now & then to make her happy. :)
Change brands of dry food. Various brands smell and taste different. Try mixing in a small amount of fresh meat, oily fish like sardines or natural unflavoured voghurt to add some interest. It may be worth talking to your vet about it too.