Keep getting null in field scripting

Elastic Stack Kibana
1

Hi, not all documents has the field "seconds", so I check for it, and then check if the value is not null, but I keep getting null results,

if (doc.containsKey('seconds')){
    if (doc['seconds'].value != null){
        return doc['seconds'].value;
    }
}

Any clues on what is happening?

the field is a number
return type number
elk 7.51

2

The return type is number only when the if is true.

To me, it looks like the script needs another return and the end, and provide a fallback when the value is null.