'Unable to determine event source based on event.' Lambda to Lambda Invoke

Hello,
I am trying to catch event parameters from Lambda A which invokes Lambda B with event parameter.

I was trying to use getCurrentInvoke() at the global level to catch it, but unfortunately it was futile.

How can I catch event parameter passed when invoked by another Lambda?

The Lambda b is for my slack app that I deployed onto Lambda.

at the end of the file it has this exports.handler

```javascript
module.exports.handler = serverlessExpress({
app: receiver.app,
});
```

I believe this is the place where I need to grab the event parameter. So far, what I've done is this :
```javascript
exports.handler = async (event, context) => {
console.log(event, context);
return serverlessExpress({
app: receiver.app,
});
};

-----------

module.exports.handler = async (event, context) => {
console.log(event, context);
return serverlessExpress({
app: receiver.app,
});
};
```
none worked out for me :(
I am very new to this serverless and backend logic stuff so please shed some knowledge! I greatly appreaciate!