Fatal error when trying to change e-mail address in admin area

Hello,

[Edit at the bottom.]

I don't know what would be the best place to report this, so I try here.

A user registered with my site, but made an error with his e-mail address. So on the "user" page in the admin area, I choose "change e-mail address".

But when I update the address, I receive a fatal error:

"count(): Argument #1 ($value) must be of type Countable|array, null given

Log at time [...] may have more data."

#0 /[...]/vendor/elgg/elgg/engine/classes/Elgg/Router.php(237): include()
#1 /[...]/vendor/elgg/elgg/engine/classes/Elgg/Router.php(172): Elgg\Router->getResponseFromFile('/[...]...', Object(Elgg\Request))
#2 /[...]/vendor/elgg/elgg/engine/classes/Elgg/Router.php(85): Elgg\Router->prepareResponse(Object(Elgg\Http\Request))
#3 /[...]/vendor/elgg/elgg/engine/classes/Elgg/Router.php(65): Elgg\Router->getResponse(Object(Elgg\Http\Request))
#4 /[...]/vendor/elgg/elgg/engine/classes/Elgg/Application.php(447): Elgg\Router->route(Object(Elgg\Http\Request))
#5 /[...]/vendor/elgg/elgg/engine/classes/Elgg/Application.php(339): Elgg\Application->run()
#6 /[...]/vendor/elgg/elgg/engine/classes/Elgg/Application.php(389): Elgg\Application::route(Object(Elgg\Http\Request))
#7 /[...]/index.php(8): Elgg\Application::index()
#8 {main}

(I added [...] where there was individual information about my site.)

Is this a bug? An error on my side? What could I do about it?

Thanks for any advice!

Edit: I decided to validate the user manually. After that I could update their e-mail address. But I would prefer it if the "change e-mail address" for newly registered, yet unvalidated users would work.