https://getsupport.atlassian.com/browse/JST-559261

And they keep two separate tickets for the same functionality. JSDCLOUD-5746 has 172 votes and this has 54. What's even more frustrating is that the clients can't even change their own email address.

JSD Cloud admin here. Redirected here by support. A "nothing I can do for you" answer to a critical issue. There needs to be some kind of solution in place here.

We just migrated tenants, into our new parent company, and our email addresses changed from janedoe@whatever.com to jane.doe@whatever.com (notice the dot). This means our internal customers, our users, completely lost access. We needed a fast solution to update everyone's email addresses; their login. Since we were not able to adjust the account email addresses, we had to create 300+ new ones. We then had to manually adjust the names of 300+ new accounts. We then had to manually adjust the names of 300+ old accounts. A week after the issue first sprung up, I still have every other project on hold while I am now manually adjusting the assignee/reporter/etc for every single user and this whole situation has now left a very bad taste in my mouth. If there isn't a customer facing solution or API method, there should at least be a backend solution for Atlassian support to assist the JSD admin.

@Angel, I agree.

This platform is riddled with similar items tho.  They've spun up Cloud (years ago) and its half baked.  Atlassian is far more interested in the look and feel, than how their tool functions.

@Devlin the fact that they call this a feature request is what concerns me. This isn't a feature, it's basic system functionality. Not only that, but it's functionality the system once had. When we first signed up with JIRA, we could mass upload our users, change their names, passwords, email addresses, and assign them with a username that matched our other systems. It really is a sad state from that now. 

Redirected by support to another stale feature request?

Yippee...

This is a pretty bog standard requirement for any ticketing system. Email addresses change all the time, company acquisitions, rebranding, etc.. 

Has there been any update from Atlassian on this?

Are we forced to create a new customer user account and lose the old history? 
Authorize at least the modification by a jira administrator from the page /admin/jira-service-desk/portal-only-customers, currently we can only update the customer's name, it is the height of absurdity.
Come on! Wake up!

Thx Adrian SMYTH for the tip 

Our company will be changing ALL of our email addresses in 2019 due to being purchased by another organization. This is about to be a very big issue for us as we need to have historic records of service tied to the correct individuals for auditing purposes. While they can continue to login using their old email addresses, they will not receive updates/notifications on their new requests. This may be enough to have us looking for a new solution. 

I've had this come up before and wanted the customer to still be able to access previous issues that were still active.

To add to the Workaround that is proposed above:

Create a new customer account (using a new email address) and Create an Organisation to re-group the old and new emails in the active tickets that still need to be followed up. This way the customer can see all their issues on the portal whether they are connected with the old or new email address.