Angular @Input value not changing when changed from Parent Component

I have added same child component three times in a single parent component

And below is the change function called on one of the children's components to change the selectedName in other two child components The @Input is type of string if I change it to object it work fine.

And this is how child component looks like

Your issue seems to be one of value vs. reference types.

The reason it works as an Object is that Objects are reference types: when you pass an Object to a component, you are passing its reference, not a "copy". That means that when you mutate that Object (in a child, for example), any component with a reference to that Object will "see" the change.

The same isn't true for value types. When you pass a string, number, or boolean to a component, you are passing the value, completely unlinked from the source variable.

You shouldn't be mutating something inside a child component which is relied upon by its siblings and/or parents. You should either be using a service (with methods for mutation) or an @Output to bubble the change event upwards from the child.