No activity in Flow portion of Hive

Has anyone else had a strong hive that does not want to expand into the Flow section? I’ve done it for 2 seasons on 2 different hives, and I get some activity in the Flow section, but they don’t cap any the cells. The cells are arranged properly with the key tool. What is wrong here?

3 posts were merged into an existing topic: How to encourage bees to fill the Flow Frames