Findone return element within document

I’ve written a function within realm, that it will input an ID and search a collection for the matching ID. So if it is successful then it will return a message

In my document it contain ID, Name.

const doc =“mongodb-atlas”).db(“ChurchRepository”).collection(“MemberDetails”).findOne(query)
.then (result => {

This is all good, I can have the result “Simon”

However if I return the function as

return "Welcome " + doc; then I get the result as EJSON.parse(’“Welcome [object Promise]”’)

Any idea?