Clicking user name requests a NAN account

In a normal stream of content when we click on a user name its sending request to a broken entity not available on the server.

The request from the frontend goes this way

https://instance.example/api/v1/accounts/NaN/statuses?exclude_replies=true

The response for above obviously is a 500 Internal Server error

Not sure what is causing this but the code on rendered HTML is as follows

<a href="https://instance.example/users/Username" target="_blank" class="status__display-name"><span class="display-name"><bdi><strong class="display-name__html">Username</strong></bdi><span class="display-name__account">@Username</span></span></a>