I need some help. It's my first try with promises.
Here is my code for the promise:

```
const deleteUniversRefInTarget = (universName, targetName) => {
  console.log('Appel de deleteUniversRefInTarget')
  const promis = new Promise((resolve, reject) => {
    Target.findOneAndUpdate({ univers: universName, name: targetName },
      (err, target) => {
        console.log('Entrée dans la promesse')
        if (err) {
          reject(err)
        } else {
          if (target === null) {
            reject(TypeError(`Invalid univers'n name ${universName}`))
          } else {  
            if (target.univers.length === 1) {
              resolve('deleteTarget')
            } else {
              target.univers.splice(target.univers.indexOf(universName), 1)
              resolve('dereferencedUnivers')
            }
          }
        }
      })
  })
  return promis
}

```

I call this promise here :

```
exports.deleteATarget = (req, res) => {
  deleteUniversRefInTarget(req.params.universName, req.params.targetName)
    .then((response) => {
      console.log('Fin du traitement de la promesse')
      if (response === 'deleteTarget') {
        Target.findOneAndDelete({ name: req.params.targetName, univers: req.params.universName },
          (err, target) => {
            if (err) {
              res.send(err)
            }
            res.json({ message: `Target ${target.name} isn't used in any univers, so we deleted it` })
          })
      } else {
        res.json({ message: `Target ${req.params.targetName} no longer used in ${req.params.universName} univers` })
      }
    })
    .catch((error) => {
      res.send(error)
    })
}

```

In the console, I can see : 
**Appel de deleteUniversRefInTarget**
But not **Fin du traitement de la promesse**

So ... do you know what I'm doing bad ?