Permitted error for snap invoking the other snap

[huweihong]

According the example https://github.com/MetaMask/snaps/tree/main/packages/examples/packages/invoke-snap , I wrote two snaps: snapA: local:http://localhost:8080 snapB: local:http://localhost:8081

snapA invoke snapB, but there is the permitted error. Are there some other configures?

[huweihong]

I added the permission in the snap.manifest.json of snapB :

 "initialPermissions": {
    "endowment:rpc": {
      "snaps": true
    },
  }, 

But there is the following error: