我有一个控制器功能，它成功地用一组联系人更新我的组文档，但问题是如果我向数据库添加另一个联系人，它会覆盖旧联系人，所以我的文档最多只能有 1 个联系人一次。有没有办法在我更新时添加新联系人而不是替换现有联系人？

这是我的控制器功能

   const createContact = async (req,res) => {
                const { phone_number,country,phone_type,group,firstName,lastName,company,email} = req.body
                
                     // we have success gotten group._id and made it into an object

                const newContact = new Contact({
                                                                          //[    // group array of objects
                                                                          //  {
                                                                          //    contacts: [],//    _id: '60d2d43345f1de1135185efe',//    title: 'vacant',//    created: '2021-07-27T19:40:01.600Z'
                                                                          //  },//  {
                                                                          //    contacts: [],//    _id: '60ff432fa2f369134d838e3c',//    title: 'yellow belts',//    created: '2021-07-26T23:20:15.933Z'
                                                                          //  }
                                                                          //]
                    phone_number: phone_number,country: country,group: group,// this group coming in is an array of objects,each object has array of contacts
                    phone_type: phone_type,firstName: firstName,lastName: lastName,company: company,email: email,_user: req.user.id
                })
                const createdContact = await newContact.save() // I now have acces to this objectId
                console.log(createdContact._id) // we need to push this into each groups contact array
                const GroupId = group.map(groups => groups._id) 
                const ChosenGroups = await (await Group.updateMany({ '_id': { $in: GroupId}},{$set: {contacts : createdContact._id}}));
                console.log(ChosenGroups)
                res.status(201).json(createdContact)
            }```