Bulk editing Closed tickets

Hey Albert,

At this time, there's no editing that can be done to Closed Tickets. The only action that can be taken is either deletion or redaction. 

However, Zendesk appears to be exploring the ability to edit a closed ticket. You can check out the topic here and upvote it if you'd like to see this feature. 

In most ticket management systems, you can typically bulk edit certain fields in a selection of closed tickets, but it depends on the specific software. While some systems may restrict editing closed tickets to maintain record integrity, many allow you to update non-critical fields like notes or labels even after closure.
for further information visit this link
https://support.zendesk.com/hc/en-us/community/posts/4409217551642-Feature-Request-Ability-to-edit-closed-tickets?page=5