Problem with input field in a FormGroup in ionic/angular

I’ve an issue with a FormGroup. I have a list of descriptions of places that I use to fill in a form with corresponding ion-input fields. The user should be able to update the description & submit it.
But when I don’t update the value in the fields, the data sent to the ts file is empty even if it’s well displayed on the screen. Can you please advise how to fix it?

Here is my html file:

<ion-content padding class="form-content" [fullscreen]="true">
    <ion-header collapse="condense">
      <ion-toolbar>
        <ion-title size="large">Debug</ion-title>
      </ion-toolbar>
    </ion-header>
  <form [formGroup]="validations_form"  (ngSubmit)="onSubmit(validations_form.value)">    
    <div *ngFor="let place of (places | async)">
      <ion-item>
        <ion-label color="primary"></ion-label>
        <ion-input type="text" formControlName="desc_{{place.id}}" [value]="place.name"></ion-input>
      </ion-item>
    </div>
    <ion-button expand="full" type="submit">Save</ion-button>
  </form>
</ion-content>

Here is my ts:

import { Component} from '@angular/core';
import { Observable } from 'rxjs';
import { Validators, FormBuilder, FormGroup, FormControl, FormArray, ValidationErrors } from '@angular/forms';
import { PersonService } from '../../person.service';
import Place from '../../types';


@Component({
  selector: 'app-debug',
  templateUrl: './debug.page.html',
  styleUrls: ['./debug.page.scss'],
})
export class DebugPage {//} implements OnInit {
  places: Observable<Place[]>;
  validations_form: FormGroup;
  constructor(
    public formBuilder: FormBuilder,
    public personService: PersonService
  ) {
    this.places = personService.getAllPlaces_full(); 
    this.validations_form = this.formBuilder.group({
      'desc_1': ['', Validators.required],
      'desc_2': ['', Validators.required],
      'desc_3': ['', Validators.required],
      'desc_4': ['', Validators.required],
      'desc_5': ['', Validators.required],
      'desc_6': ['', Validators.required]});
   }

onSubmit(values){ 
    console.log(values);
    for (let [key, value] of Object.entries(values)) {
      if (!( value ===null))
      {
        console.log(`${key}: ${value}`);  
      }
    }
  }
}

Here is the screen:
form

Here is the log: