Dynamic Route Matching with cutom regular expression is not working

Hello All,
I’m trying to implement dynamic route matching with custom regular expression in my vue application.
But it is not working.

Here is my code.

  1. UserView.vue

  1. router.js

  1. PageUserDetail.vue

My requirement is, I need to show either userID or userName value in the user detail page.
I don’t want to display both values at a time.

When user click on “Dumy user” link then in detail page it should display only,

Selected User Name: Ram

If user click on list item then it should display only
Selected User ID : 1

and so on.

I’m getting below warning message like,

After clicking on Dummy user link. it shows like,

Can anyone help me?