invalidcharactererror: failed to execute
[(ngModel)]="model.description"] // ']' is added unnecessarily
change it to
[(ngModel)]="model.description"
Don't wrap it to a square bracket.
Update:
You can initialize your model variable as follow according to your need,
model:ModalComponentModel=<ModalComponentModel>{};
OR
model:ModalComponentModel=<ModalComponentModel>[];