* ngFor with ngModel and value

I have the following repeat structure:

TS

  resposta: string[];

HTML:

<ion-card *ngFor="let pergunta of perguntas; let i = index">

I have a ngModel that I need to print the value of it in its value:

<ion-textarea name="resposta" [(ngModel)]="resposta[i]" value="{{resposta}}" placeholder="Resposta" clearInput></ion-textarea>

But I get:

  

Can not read property '0' of undefined

If I do: [(ngModel)]="response" all happens fine, but my other elements also get the value I put in that field.