OtherInstance.save is not a function [hasOne Association]

[DimitarDechew]

Yo guys,
I'm trying to change the group of item using hasOne association, but apparently I cannot do that. I'm getting this error:

/home/ghostbg/Projects/qsell-project/node_modules/orm/lib/Associations/One.js:253
        OtherInstance.save({}, { saveAssociations: false }, function (err) {
                      ^

TypeError: OtherInstance.save is not a function
    at Object.value (/home/ghostbg/Projects/qsell-project/node_modules/orm/lib/Associations/One.js:253:23)
    at /home/ghostbg/Projects/qsell-project/controllers/device.js:19:14
    at /home/ghostbg/Projects/qsell-project/node_modules/orm/lib/ChainFind.js:212:16
    at /home/ghostbg/Projects/qsell-project/node_modules/orm/lib/ChainFind.js:88:16
    at /home/ghostbg/Projects/qsell-project/node_modules/async/dist/async.js:1140:9
    at /home/ghostbg/Projects/qsell-project/node_modules/async/dist/async.js:473:16
    at iteratorCallback (/home/ghostbg/Projects/qsell-project/node_modules/async/dist/async.js:1064:13)
    at /home/ghostbg/Projects/qsell-project/node_modules/async/dist/async.js:969:16
    at /home/ghostbg/Projects/qsell-project/node_modules/async/dist/async.js:1137:13
    at Object.<anonymous> (/home/ghostbg/Projects/qsell-project/node_modules/orm/lib/Model.js:127:16)
    at /home/ghostbg/Projects/qsell-project/node_modules/orm/lib/Instance.js:32:10
    at Array.map (<anonymous>)
    at emitEvent (/home/ghostbg/Projects/qsell-project/node_modules/orm/lib/Instance.js:31:19)
    at /home/ghostbg/Projects/qsell-project/node_modules/orm/lib/Instance.js:768:7
    at process._tickCallback (internal/process/next_tick.js:61:11)

Here's my code:

  update: async function(m, db, socket) {

    var targetCluster = db.models.cluster.findAsync({ id : m.targetCluster });

    db.models.device.find({ id : m.deviceID }).first(function(err, device) {
      if(err) throw err;

      device.setCluster(targetCluster, function(err) {
        if(err) throw err;
      })
    })

  }