The `serverless deploy` doesn't update any cloudformation after upgrading to v3

I have just upgraded my project to v3 Serverless Framework and have some changes on the serverless.yml file to satisfy v3 requirements.
When I run the serverless deploy command, everything seems good. But I don’t see any updating on cloudformation as well as lambada function.
The result after I execute the command:

$ serverless deploy --stage dev
config.options_stage: dev
serverless.service.custom.stage: undefined
serverless.service.provider.stage: dev
config.stage: dev

Deploying xxx to stage dev (ap-northeast-1)

✔ Service deployed to stack xxx-dev (0s)

I also tried to make tiny code changes on each function, But still the same, nothing changes.

Please help me if you have any ideas. Thanks!