ERROR Error: No value accessor for form control with name: - angular-reactive-forms

Question

I have followed
the following guide
Angular-Reactive forms
I modified a bit the code to put it in a module, adding some fields to the originals model and it worked.
after upgrading to angular 8, the module is still working, but the console in Chrome for every control gives me this error:core.js:6150 ERROR Error: No value accessor for form control with name: 'title' at _throwError (forms.js:2603) at setUpControl (forms.js:2377) at FormGroupDirective.addControl (forms.js:5699) at FormControlName._setUpControl (forms.js:6274) at FormControlName.ngOnChanges (forms.js:6219) at FormControlName.rememberChangeHistoryAndInvokeOnChangesHook (core.js:1506) at callHook (core.js:2525) at callHooks (core.js:2492) at executeInitAndCheckHooks (core.js:2443) at selectIndexInternal (core.js:8389)
this is my code for question-form-component.html:
<div [formGroup]="form">
<label [attr.for]="question?.key">{{ question?.label }}</label>
<div [ngSwitch]="question?.controlType">
<input
ngDefaultControl
*ngSwitchCase="'textbox'"
[formControlName]="question?.key"
[id]="question?.key"
[type]="question?.type"
[value] = "question?.value"
/>
<div [ngSwitch]="question?.controlType">
<ion-textarea
ngDefaultControl
*ngSwitchCase="'textArea'"
[formControlName]="question?.key"
[id]="question?.key"
autoGrow="question?.autoGrow"
[value]= "question?.value"
></ion-textarea>
</div>
<div *ngSwitchCase="'barcodeScanner'">
<app-barcode-scanner
[formControlName]="question?.key"
(ngModelChange)="question?.onChange($event)"
[id]="question?.key"
[value]="question?.value"
></app-barcode-scanner>
</div>
<div *ngSwitchCase="'datebox'">
<ion-datetime [formControlName]="question?.key" [id]="question?.key">
</ion-datetime>
</div>
<div *ngSwitchCase="'switchBox'">
<p class="switchText">
{{ getValue ? question.labelTrue : question.labelFalse }}
</p>
<ion-icon
[name]="getValue ? question.iconTrue:question.iconFalse"
></ion-icon>
<ion-toggle
[formControlName]="question?.key"
[id]="question?.key"
></ion-toggle>
</div>
<div
[formControlName]="question?.key"
[id]="question?.key"
>
<div *ngSwitchCase="'itemSelector'"
[formControlName]="question?.key"
[id]="question?.key"
ngDefaultControl
>
<app-selector-items
[formControlName]="question?.key"
[id]="question?.key"
[text]="question?.text" [service]="question?.service" (selectedItem)="question.selectedItem($event)"
[sorterFunction]="question?.sorterFunction"
[filterFunction]="question?.ItemsFilterFunction"
[createPopup]= "question?.createPopup"
[item]="question?.value"
(selectedItem)="question.selectedItem($event)" >
</div>
<select
[id]="question?.key"
*ngSwitchCase="'dropdown'"
[value]="question?.value"
[formControlName]="question?.key"
>
<option *ngFor="let opt of question?.options" [value]="opt?.value">{{
opt.key
}}</option>
</select>
<div *ngSwitchCase="'geobox'">
<input-geolocation
[id]="question?.key"
[address]="question.value?.adress"
[formControlName]="question?.key"
(ngModelChange)="question?.onChange($event)"
></input-geolocation>
</div>
{{ question ? question.label : "" }} is required
this is my question-form-component.ts:
import {
Component,
Input,
OnInit,
Output,
EventEmitter,
ChangeDetectionStrategy,
ɵConsole,
OnChanges,
SimpleChanges
} from '#angular/core';
import { FormGroup, FormControl } from '#angular/forms';
import { QuestionBase } from '../../models/question-base';
#Component({
selector: 'app-question',
templateUrl: './question-form-component.html',
changeDetection: ChangeDetectionStrategy.OnPush
})
export class QuestionFormComponent implements OnInit, OnChanges {
public value: any;
#Input() question: QuestionBase;
#Input() form: FormGroup;
ngOnInit() {
this.value = this.question ? this.question.value : undefined;
this.form = this.form
? this.form
: new FormGroup({
// I need an instance of formgroup for run the tests
name: new FormControl(this.question.key),
value: new FormControl(this.question.value)
});
}
ngOnChanges(changes: SimpleChanges) {
}
get isValid() {
return this.question ? this.form.controls[this.question.key].valid : false;
}
get getValue() {
return this.question.key ? this.form.get(this.question.key).value : '';
}
getIcon() {
return this.form.get(this.question.key).value ? String(this.question.iconTrue) : String(this.question.iconFalse)
}
}
thanks in advance