How to clear Validate when using with FormControlName

 Hi Guys,When i using ng-select in Reactive Form. My formControlName has: ng2SelectEmptyError: {valid: false}. I do not want it cause that formControl is option not required.
Help me please !

`asyncValidator: null
dirty: (...)
disabled: (...)
enabled: (...)
errors:
ng2SelectEmptyError:
valid: false
__proto__: Object
__proto__: Object
invalid: true