How to Get Finches to Feed from a Bird Feeder
Birds are creatures of habit and can take a while to adapt to a new feeder. Give your birds some time to adjust.
Make sure you put fresh seed in your bird feeder. Nyjer seed can go rancid in hot weather, so if you are using that, buy it in small batches and store in a cool, dry place.
Try tying some sticks on the perches, but leave a few perches without sticks. Finches will land on the sticks, which will be like the perches they are used to, and then they should eat the seed. Other finches will see them eating and may land on the perches, and then they may hopefully try the seed from the portals at these perches. Finches like to feed in flocks, so finches will be motivated to try landing on the perches without sticks. Once they get the hang of it, you can remove the sticks and you will have trained your finches to accept the new perches.