wp default login page

Hi

I am using version 6.3.6 of this plugin and noticed that sometimes the login page reverts to the standard wp login page. The login link chnages to /wp-login.php

This has never been the case before and I don’t know why it just started doing this. Can anyone shed some light on this?

Thanks

https://www.ads-software.com/extend/plugins/theme-my-login/