Looks like you didn’t change SECRET_NAME to your Secret name with Private App token.
I’ll walk you through.
Navigate to HubSpot Settings
In Left menu find INTEGRATIONS > PRIVATE APPS
Click Crate a Private app button
In Basic Info give it a name - ex. Contact
In Scopes in CRM find crm.objects.contacts and select Read and Write for it
Click Create App button and Continue creating in pop-up
Click Show token and Copy
Now go to you Custom Code step in workflow
Second from Top there is a Dropdown list with Secrets, click it
Click Add Secret,
Give it a name best would be same as you gave to you Private App ie. Contact so you know what is what
In Secret Value paste token you copied from Private App. And Save it.
Now go to your code and change this
accessToken: process.env.SECRET_NAME
to this
accessToken: process.env.Contact