Epic Link returns error when sorted in issue navigator

Summary

As described in title, attempting to sort the epic link column/field now returns the 'An unknown error occurred while trying to perform a search.' error.

Steps to Replicate

1. Click on the 'All Issues' filter at the side to display all projects.
2. Add the 'Epic Link' column to the search results.
3. Sort the 'Epic Link' column by clicking it.

Expected Behavior

Issues displayed sorted based on epic link.

Current Behavior

'An unknown error occurred while trying to perform a search.' is shown instead.