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AHA! I figured it out. The rope was not all the way repaired. I had to drop the villager on the rope again to finish repairing the rope.
The rope (lei) should look like this before adding the flowers to it:

Now that the rope is repaired, using the cloth leaning against the sewing hut, I can pick the flowers by following the hummingbird and grabbing a flower with an adult villager.