How do I access the values of JS Objects by keys without storing in a variable?

So, I ran into a weird bug in javascript.

const obj1 = await chartService.callAPIConversion({ unix_timestamp: Math.floor(activity[0].createdAt.getTime() / 1000) })

console.log(obj1.usd_price);
//THIS WORKS -> returns proper value

console.log(await (chartService.callAPIConversion({ unix_timestamp: Math.floor(activity[0].createdAt.getTime() / 1000) })).usd_rate);
//THIS DOESNOT WORK -> returns undefined

Why am I not able to get the key without using a variable?