I will try to explain this as best as I can.
I have a select in my form which the user can chose between multiple contracts, once he choses one of them, I want to remove items from the selected contract before saving it.

The contract has and id, name, etc .. and a list of roles, for now I want to be able to keep only one role in that list so I will have to remove the other roles before saving.

Here’s what my select looks like:

<v-autocomplete
   v-model="contract"
   :items="contractsData"
   item-text="name"
   hide-details="auto"
   light
   solo
   dense
   clearable
   return-object
></v-autocomplete>

The contract that is selected here is a an object that looks like this:

{
    "id": "id-contract-001",
    "name": "contract1",
    "roles": [
      {
        "id": "id-role-001",
        "name": "admin",
        "description": "can view, create, update & delete"
      },
      {
        "id": "id-role-002",
        "name": "operator",
        "description": "can view & create"
      },
      {
        "id": "id-role-003",
        "name": "user",
        "description": "can only view"
      }
    ]
},

Here’s the method I tried to do to keep only the role I want to keep:

getContractUserRole(contract) {
  let rolesList = contract.roles
  rolesList.forEach((role) => {
    if (role.name === 'user') {
      this.contract = {
        id: contract.id,
        name: contract.name,
        roles: [
          {
            id: role.id,
            name: role.name,
            description: role.description,
          },
        ],
      }
    }
  })
},

And I am calling this method in my post request :

await this.$axios
          .$post(uri, {
            username: this.username,
            firstname: this.firstname,
            lastname: this.lastname,
            email: this.email,
            password: this.password,
            contracts: this.getContractUserRole(this.contract),

I have to add that I can’t just put role.id and role.name to the role I want to keep because in each contract the role.id is different so I have to search for the role in the selected contract.

When I try to use this method I get an error Cannot read properties of undefined (reading 'forEach'), I know for a fact that all my contracts have roles so I don’t understand exactly what’s missing ? Maybe my approach is not the best, does anyone know the best way I can do this ?

EDIT: added more details to the question.