ResourceNotFoundException: Requested resource not found

I'm trying to access DB from one AWS account to another AWS account. I did a STS call and got the AccessID and Key with Session as well. I set the Credentials in DynamoDB object. When i trigger a call with scan, i'm reading an error as

ResourceNotFoundException: Requested resource not found

ResourceNotFoundException: Requested resource not found at Request.extractError (/app/node_modules/aws-sdk/lib/protocol/json.js:51:27) at Request.callListeners (/app/node_modules/aws-sdk/lib/sequential_executor.js:106:20) at Request.emit (/app/node_modules/aws-sdk/lib/sequential_executor.js:78:10) at Request.emit (/app/node_modules/aws-sdk/lib/request.js:688:14) at Request.transition (/app/node_modules/aws-sdk/lib/request.js:22:10) at AcceptorStateMachine.runTo (/app/node_modules/aws-sdk/lib/state_machine.js:14:12) at /app/node_modules/aws-sdk/lib/state_machine.js:26:10 at Request.<anonymous> (/app/node_modules/aws-sdk/lib/request.js:38:9) at Request.<anonymous> (/app/node_modules/aws-sdk/lib/request.js:690:12) at Request.callListeners (/app/node_modules/aws-sdk/lib/sequential_executor.js:116:18)

const AWS = require('aws-sdk');

const roleToAssume = { RoleArn: 'arn:aws:iam::00000000000:role/XXXXXXX-role',
    RoleSessionName: 'session1' };

// Create the STS service object
const sts = new AWS.STS({ apiVersion: '2011-06-15' });

async function getDocumentClient() {
    const data = await sts.assumeRole(roleToAssume).promise();
    const options = { region: 'us-east-1',
        accessKeyId: data.Credentials.AccessKeyId,
        secretAccessKey: data.Credentials.SecretAccessKey,
        sessionToken: data.Credentials.SessionToken };

    AWS.config.update(options);
    if (process.env.DYNAMO_DB_ENDPOINT) {
        return new AWS.DynamoDB.DocumentClient({
            endpoint: process.env.DYNAMO_DB_ENDPOINT
        });
    }
    return new AWS.DynamoDB.DocumentClient();
}

And the other file calls this nodejs file

const Joi = require('@hapi/joi');
const getDocumentClient = require('../util/getDocumentClient');
const verifyApiAccessPermissions = require('../authentication/verifyApiAccessPermissions');

const documentClient = getDocumentClient();

async function scanPrimaryTable(exclusiveStartKey) {
    console.log('===> Into scanPrimaryTable <===');
    // console.log(documentClient);
    const result = await documentClient.scan({
        TableName: process.env.PROXIES_TABLE_NAME,
        Limit: process.env.PAGINATION_LIMIT,
        ExclusiveStartKey: exclusiveStartKey
    }).promise();
    console.log('===> Into Result <===');
    console.log(result);
    return result;
}

async function getProxies(lastEvaluatedKey) {
    const exclusiveStartKey = lastEvaluatedKey ? {
        name: lastEvaluatedKey
    } : undefined;

    return scanPrimaryTable(exclusiveStartKey);
}

async function handler(request, h) {
    const lastEvaluatedKey = request.query.lastEvaluatedKey;
    const result = await getProxies(lastEvaluatedKey);
    const proxies = result.Items;

    const permittedResponse = await verifyApiAccessPermissions(proxies, request.auth.credentials);

    if (result.LastEvaluatedKey) {
        const link = `</proxies?lastEvaluatedKey=${result.LastEvaluatedKey.name}>; rel=next`;
        return h.response(permittedResponse)
            .code(206)
            .header('Link', link);
    }

    return h.response(permittedResponse);
}