How can I access and set value to struct properties with his name as String

Question

I want to access to structure properties with its name as String . Let me explain

I can create and access to structure properties like below perfectly

Example Struct

struct MyStruct{
    var property1 : String?
    var property2 : String?
    ....
}

var obj = MyStruct()
obj.property1 = "value1"

my backend api sending to me the properties name from server . It something like :

 {
 "variable1" : "bla bla"
 "variable2" : "bla bla"
 ....
 }

I'm getting this values and do some operations and setting my structure.

Sending model and fetching model are not same by the way.Its just an example

In my situation , I'm sending this structure to server api and imagine this structure has lots of properties. Everytime when I do some operations and sending to server on app I dont want to use to set model like that.

obj.variable1 = "gettingValueFromUser2"
obj.variable2 = "username"
obj.variable3 = "bla bla"
....

I have already have property names. How can I set this structure properties like

func setProp(propName : String , propVal : String){
    //propName is "variable1"
    obj.propName = propVal 
}

I know I can do using class with KVP but I need to use with structure