Due to the size of this import (over 2k encounters) it’s taking a long time for the task to delete. For each additional time the delete import button is clicked, it triggers a second task to begin and creates a snowball effect. The link back to the adoption page is a separate bug that’s caught up in this one.
Make sure your users know to limit their bulk imports to 100-200 encounters at a time to prevent these kinds of lags. You can refer them to our Bulk Import Cheat Sheet, Bulk Import help docs, and the Bulk Import training YouTube playlist to reinforce good habits.