batchGet method not working

Hi Team,
I have trying to get batch of record. But I'm unable to fetch the record and getting the below error and code.
Please help on that issue.

My Below code
import AWS, { DynamoDB } from 'aws-sdk';
const docClient = new AWS.DynamoDB.DocumentClient();

const keyMap = await custIDs.map((element: any) => {
return { customerId: element.mergeCustId.toString(), vehicleId: element.mergeCustId.toString() };
});
console.log("keyMap", JSON.stringify(keyMap));
const params = {
RequestItems: {
'eos-dev-Customer-Vehicles': {
Key: keyMap,
}
}
};
console.log("params", JSON.stringify(params));
return docClient.batchGet(keyMap, (err: any, data: any) => {
if (err) {
console.log("err", err);
} else { console.log("data", data); }
});

Error:

2023-07-11T10:39:32.993Z a89ddd1c-c372-468c-a9d2-a91173ab9a82 INFO err MissingRequiredParameter: Missing required key 'RequestItems' in params
at ParamValidator.fail (/var/task/output/purge-merge-automation/index.js:22005:37)
at ParamValidator.validateStructure (/var/task/output/purge-merge-automation/index.js:22016:14)
at ParamValidator.validateMember (/var/task/output/purge-merge-automation/index.js:22043:21)
at ParamValidator.validate (/var/task/output/purge-merge-automation/index.js:21989:10)
at Request.VALIDATE_PARAMETERS (/var/task/output/purge-merge-automation/index.js:19767:42)
at Request.callListeners (/var/task/output/purge-merge-automation/index.js:25757:20)
at callNextListener (/var/task/output/purge-merge-automation/index.js:25747:12)
at /var/task/output/purge-merge-automation/index.js:19721:9
at finish (/var/task/output/purge-merge-automation/index.js:14369:7)
at /var/task/output/purge-merge-automation/index.js:14387:9
at EnvironmentCredentials.get (/var/task/output/purge-merge-automation/index.js:14925:7)
at getAsyncCredentials (/var/task/output/purge-merge-automation/index.js:14381:24)
at Config.getCredentials (/var/task/output/purge-merge-automation/index.js:14401:9)
at Request.VALIDATE_CREDENTIALS (/var/task/output/purge-merge-automation/index.js:19716:26)
at Request.callListeners (/var/task/output/purge-merge-automation/index.js:25753:18)
at Request.emit (/var/task/output/purge-merge-automation/index.js:25729:10) {
code: 'MissingRequiredParameter',
time: 2023-07-11T10:39:32.990Z
}

Start with the TypeScript snippet in the issue and the AWS DynamoDB DocumentClient batchGet entry point; compare the arguments shown with the API's expected request structure. Reproduce the reported MissingRequiredParameter error and confirm the intended example behavior before documenting or correcting the example.

Written by the indexing model from the issue text.