Trying to run ember addon for ember engine. "ember s" working proper and app is getting build proper

Hello community, Got stuck in this. Any advice would help

The error:

Uncaught Error: Could not find module ember-metal/computed

Probably means that your app or some addon that your app uses is trying to use an API in Ember that has since been removed.

First search for “ember-metal/computed” in your app code to rule that out. Then search through your node_modules folder to see which addon is responsible. When you find it, see if it already has a newer version that fixes this problem.

In package.json file, I have removed vector sign “ember-data-contentful”: “^0.2.0”, It works magically.