The shoe shields could be the issue. Did you fit the plastic spacer under the cleat, on top of the shoe shield?
When I used CB on a pair of Shimano trekking shoes they didn’t need the plastic spacer. But the sole of the shoe was a bit worn. Some new Giro shoes, so I fitted shoe shields to save the sole, but had to faff with the spacers, and had to trim them to the same profile as the cleats to get the wings of the pedals to clip over the cleat properly. I then had horrible hot spots because the shoes were floating above the cage of the Candy pedals and offered no support.
Now gone back to Shimano SPDs after years on CB. But struggling with the different clip in / out technique. I like the anyway in of the CB pedals. Forward, backward, stamp.