Nested loop returns last 2 values

I’m trying to send multiple items to multiple contacts in my contacts list , I use nested loop but it only send the last item for each contact ignoring the rest of the items , I didn’t know what I’m doing wrong.

here are my arrays :

ContactList = ['john','jem'];

itemList = [
    {
        "ItemTo": '[e-mail]',
        "ItemType": 'type1'
    },

    {
        "ItemTo": '[e-mail]',
        "ItemType": 'type2'
    }
]

here is my JS code :

onClick() {
    for (let i = 0; i < this.ContactList.length; i++) {
        for (let j=0; j<this.itemList; j++){
            let messageToSend = this.extractMessageDetails(
                this.ContactList[i], 
                this.itemList[j]
            );
        }
    }
} 

extractMessageDetails(contact, item) {

    const ItemTo = contact.contactId;
    const ItemType = item.type;

    const itemToSend  = {
        "ItemTo": ItemTo,
        "ItemType": ItemType
    }
    
    return itemToSend; 
}

Answer

Create an array messagesToSend = [] outside the second loop and then inside the 2nd loop push your object in that variable messagesToSend.push(this.extractMessageDetails(this.ContactList[i], this.itemList[j]););. So in the end of your second loop you will have messages for each contact

for (let i = 0; i < this.ContactList.length; i++) {
    let messagesToSend = [];
    for (let j = 0; j < this.itemList; j++) {
      messagesToSend.push( 
        this.extractMessageDetails(this.ContactList[i], this.itemList[j]););
    }
    ///send messages to contract[i]
  }

If you want to collect all messages for all contracts move declaration of array outside the loops