can not connect to ws://127.0.0.1:9944 on latest substrate-contracts-node

[JohnRioDefi]

Hello,

I just downloaded and built the latest substrate-contracts-node and run it using the command: substrate-contracts-node --dev

Then open this URL in the browser on the same machine: https://paritytech.github.io/contracts-ui/#/?rpc=ws://127.0.0.1:9944

but it says can not connect to ws://127.0.0.1:9944 as following showed:

Could anyone help to solve this? Thanks!