Are you using the same resume each time you apply? Maybe try and change up the structure or what you're saying. It sounds like whatever you have on your resume isn't getting enough views
Agreed, but I would also find a way to handle the answer gracefully. I think saying something like you were looking for other opportunities or that you weren't being challenged.
Always frame your departures in a way that shows you are a good worker and you're looking to do more not less.