If you have setup a custom login URL for the live site WP admin, then you will need to add custom login URL for staiging site also, kindly follow the steps below
Step 1: Go to WP Plugin Settings -> Staging Tab and enter the custom login link, as shown in the image below
Step 2: Click Save Changes.
Step 3: After the staging process visit the staging site staging site custom login, eg: https://mysite/staging/custom-login, to login to the staging site admin.
![](https://firebasestorage.googleapis.com/v0/b/hndesk-prod.appspot.com/o/docs%2F5b975a8dff056b6ff9fcaccb%2F5e6f62f529de1103ebc3d7a8%2F1584358614251_screenshot-newtab-2020.03.16-17-05-59.png?alt=media&token=50a5cfa4-862b-45b6-a80f-2d4f48969eca)