Ion-datetime issue with [(ngModel)] in non-root page

In my tab application using ion-datetime with [(ngModel)] and initialize it and read from it doesn’t make any issues.
but when i’m in a child page [(ngModel)] seems to give me this error
Error: No value accessor for ‘’
<ion-datetime displayFormat=“MM/DD/YYYY” [(ngModel)]=“dateOfBirth” >
and hence I can’t initialize the datetime , it always shows 1-1-2016
I did workaround to get the value picked and save it in storage by using
(ionChange)=“dateOfBirthChanged($event)” insted of [(ngModel)] ,
but still can’t give it an initial date that is saved in storage

any help, or should I try Native date picker ?