Lambda works locally but not when deployed

Question

I'm using serverless framework and my endpoint work locally with sls offline, but when I sls deploy it to AWS I get 502 Bad Gateway in postman 

and if I go to AWS Lambda console and click test event to see what comes up I get

{
  "errorType": "Runtime.UserCodeSyntaxError",
  "errorMessage": "SyntaxError: Unexpected token '??='",
  "trace": [
    "Runtime.UserCodeSyntaxError: SyntaxError: Unexpected token '??='",
    "    at _loadUserApp (/var/runtime/UserFunction.js:222:13)",
    "    at Object.module.exports.load (/var/runtime/UserFunction.js:300:17)",
    "    at Object.<anonymous> (/var/runtime/index.js:43:34)",
    "    at Module._compile (internal/modules/cjs/loader.js:1085:14)",
    "    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1114:10)",
    "    at Module.load (internal/modules/cjs/loader.js:950:32)",
    "    at Function.Module._load (internal/modules/cjs/loader.js:790:12)",
    "    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:75:12)",
    "    at internal/main/run_main_module.js:17:47"
  ]
}

There's nothing in my code that has ??=' in it so I made my endpoint super simple as a process of elimination and returned a response instantly ie

router.get('/my-api', async (req, res: Response) => {
    return res.status(200).json({"message": "success"});
});

but I still get the same error. serverless.yaml

service: my-service

plugins:
    - serverless-webpack
    - serverless-offline

custom:
    env:
        default: Sandbox
        prod: Production
        AWS_REGION: us-east-1

    apigwBinary:
        types: #list of mime-types
            - '*/*'

    contentCompression: 14000

    webpack:
        webpackConfig: ./webpack.config.js
        packager: 'npm'
        includeModules:
            forceExclude:
                - aws-sdk
                - dotenv

provider:
    name: aws
    versionFunctions: false
    region: ${opt:region, 'us-east-1'}
    stage: ${opt:stage, 'staging'}
    environment:
        STAGE: ${self:provider.stage}
functions:
    myApi:
        handler: src/handler.service
        events:
            - http:
                  path: route/my-api
                  method: GET
                  cors: true

handler.ts

import { APIGatewayProxyEvent, Context, ProxyResult } from 'aws-lambda';
import awsServerlessExpress from 'aws-serverless-express';
import app from './app';

const server = awsServerlessExpress.createServer(app);

export function service(event: APIGatewayProxyEvent, context: Context) {
    return awsServerlessExpress.proxy(server, event, context);
}

So as a recap, it works locally, but not after sls deploy in AWS in postman or aws console lambda test event. So if it works locally, why isn't it working in aws. I appreciate any help!