A strange problem about solid

First I make this

It works fine like this:

Then I add the Solid behavior to both A and B.

But it shows like this:

I just couldn't figure it out. Can I keep solid behavior while they can bouncing in the middle area?

The any other platform values of A and B are all the same.

Thanks.

You really shouldn't use platform as solid. It's like adding two fade behaviors, eventually one will cancel out the other.

You could try pinning a separate solid object to each platform object.

What are you trying to accomplish? Why do they need to have the solid behavior?