Controller 'ngModel', required by directive 'ngModel', can't be found! when using md-dialog

[Nagendra080389]

Here is a CodePen of the issue I am facing.
When ever I click 'Open' button I get a error in chrome console log.
I am not sure, why is this happening though.

[Gillardo]

Dunno what you are doing here but i get an error when i press the first Open button that appears on the page.

[joelmuskwe]

Getting same error i copied the logic for ctrl.picker2 both the javascript and html into my angularjs application and i am using version 1.8.2 and getting the same error Controller 'ngModel', required by directive 'ngModel', can't be found!

[victormcfreire]

Getting the same error here. The datepicker and ngModel are on the same input element but the error still occurs. Everything still works fine, tho. According to some research I made, this is due to the fact that the directive 'datetime-picker' loads the template in templateCache, so it is possible that it loads before getting the actual ngModel. I've tried many ways to solve this, but I couldn't.
I'm using angular 7 and angular-ui-bootstrap 2.5.0