Remove validators from form control Angular 6

You can try following as another solution if you want to remove validator from your field:

public saveDraft(): void {
   this.addProjectForm.get('title').clearValidators();
   this.addProjectForm.get('title').updateValueAndValidity();
}

Try this:

this.addProjectForm.get('title').setValidators([]); // or clearValidators()
this.addProjectForm.get('title').updateValueAndValidity();

If you want to add a validator then append array of validators:

this.addProjectForm.get('title').setValidators([Validators.required]);
this.addProjectForm.get('title').updateValueAndValidity();

Note: You have to use updateValueAndValidity() after each change

I have tried all of above, But for me following code has worked.

let formControl : FormControl = this.formGroup.get("mouldVendor") as FormControl;
formControl.clearValidators();
formControl.setValidators(null);
formControl.updateValueAndValidity();