Fetching Not-Authorized Error in Airtable Integration

I’m getting the following error when I get or create the data from airtable in my next.js project.

AirtableError {
  error: 'NOT_AUTHORIZED',
  message: 'You are not authorized to perform this operation',
  statusCode: 403
}

I’m using airtable npm module for integration.

I’ve added all required scopes already but not sure why I am getting that error.
Can anyone help me for that? Thanks