Error: ConfigError: Missing region in config

The SDK could not resolve a Region for the DynamoDB client. Configure the Region containing your table, either on the client or through the selected AWS profile and environment.

import { DynamoDBClient } from "@aws-sdk/client-dynamodb";
const client = new DynamoDBClient({ region: "eu-west-1" });

For a profile-based setup, check aws configure get region --profile work and ensure the application selects that profile. A terminal environment is not automatically inherited by every desktop application or service process.

DynamoDB Local still requires a signing Region even when you set an endpoint URL. See DynamoDB Local configuration or the SDK Region guide.