Select multiple contacts using search for a selected account while creating a record for custom object

Question

I am using an aura component where I have a requirement where I need to select multiple contacts for a particular account to create a record in custom object.

This is possible while editing record for custom object.

let editRecordEvent = $A.get("e.force:editRecord");
editRecordEvent.setParams({
                          recordId: event.id
                          });

This is only while editing of record. As i'm able to select multiple contacts and could save record. I want to achieve same while creation of record.

For Creation of record I'm using a custom popup modal. In that I could see the list of Contacts but not able to select multiple contacts. If I select one of the contacts the search box disappears and I'm only able to select a single contact.

This is peice of code for above image.

<div class="slds-col slds-size_6-of-12">
    <span>
       <c:ParentComponent  
            objectAPIName="Contact" 
            IconName="standard:contact"
            ConId="{!v.ConId}"
            accountDetail="{!v.selectesRec.AccountId__c}"
            selectedRecord="{!v.selectedLookUpRecord}"
            label="{!$Label.c.ContactName_Label}"
      />
    </span>
</div>

I guess I'm missing something but not able to figure it out completely. I have gone through various links as well but could not find suitable hint for this problem.

Any hint or support would be helpful.