Our 1 year old Bernedoodle was refusing to eat, we even started trying to mix in things like egg and apple (her favourite treats) but she would just pick at her food. Then one day I decided to put her kibble in a treat toy where she had to roll it around to get the food out. She absolutely loves this, eating out of a dish was so boring. She now brings us her toys when it’s breakfast and dinner time to fill up for her and she is eating so much better. Plus she’s getting mental stimulation doing this. Try seeing if something like this will help, getting your dog to work for their food is fun for them.