WSK API Create endpoint ceases to work after few days

We've created a simple Adobe I/O Runtime action, developed using NodeJS, and successfully deployed our web push integration with Adobe Campaign Standard.
We used the Project Firefly template for the runtime project and used the Campaign STAGE instance for this integration.
The application uses serverless deploy method.

This is fine as expected and we are able to send web push notifications from our ACS instance

The issue we're facing is that "wsk api create" commands generate API endpoints that are only available for a few days, after we've noticed that the endpoint of the API returns the 404 exceptions, and again we need to redeploy the application and generate the API endpoint

When we've been observing the behaviors, it's basically changing the one alphabet at the endpoint. Rest remains the same. 
How do we generate a static endpoint which basically doesn't change dynamically? The thing is every time the endpoint changes we need to change the respective ACS workflow