I am using a try-catch in my typescript where I can see the error in the browser console but when I try to convert to string it loses the important part.

the code looks like below:

try{ }catch(err:any){
      console.log("error in add asset", err)
      const payload = this.core.reportError(err, this.MODULE_NAME + " line#819")
      console.log("err payload is::::", payload)
}

  reportError(err:any, location: string){
    let msg = ""

    if(err === undefined || Object.keys(err).length === 0){
      msg = "" 
    }else{
      msg = JSON.stringify(err)
    }

    let email = ''
      if(this.userData.profile !== undefined && this.userData.profile.email !== undefined){
        email = this.userData.profile.email
      }

      const payload = {
        date: (new Date()).getTime(),
        error: msg,
        uid: this.userData.profile.uid,
        location: location,
        email: email
      }
      
      return payload
  }

What it prints in the console is:

[Log] error in add asset – FirebaseError: [code=invalid-argument]: Function setDoc() called with invalid data. Unsupported field value: undefined (found in field finance.assets.Saving.`1719576795123`.`Tax Free Growth` in document users/KshJnfF9hbgs7jWWwXwXuHRxDWY2) 

[Log] err payload is:::: 
Object
date: 1719576795138
email: "xyz"
error: "{"code":"invalid-argument","name":"FirebaseError"}"
location: "add-asset.component.ts line#810"
uid: "KshJnfF9hbgs7jWWwXwXuHRxDWY2"

So, the err payload eats up the real detailed error in doing JSON.stringify and I am confused why