TypeError: Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher::dispatch()

Problem/Motivation

After saving a task I get the following:
"The website encountered an unexpected error. Please try again later."

If I close the error and go back to the project backlog the Task was created despite the error message.

Steps to reproduce

Create a project
Visit backlog and create a task
Save task and get "The website encountered an unexpected error. Please try again later."
Visit backlog page and view the newly created task (despite the error the task was created)

The error message after task save

Location 	/burndown/task/add/task?destination=%2Fburndown%2Fbacklog%2FWILD&shortcode=WILD

Referrer 	/burndown/task/add/task?shortcode=WILD&destination=/burndown/backlog/WILD

Message 	TypeError: Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher::dispatch(): Argument #1 ($event) must be of type object, string given, called in \modules\contrib\burndown\burndown.module on line 336 in Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher->dispatch() (line 89 of \core\lib\Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher.php).

In my backlog where my newly created task is visible
I can click on "send task to board" I get the same "The website encountered an unexpected error. Please try again later." message

Location 	/burndown/api/backlog/send_to_board/WILD-1

Referrer 	/burndown/backlog/WILD

Message 	TypeError: Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher::dispatch(): Argument #1 ($event) must be of type object, string given, called in \modules\contrib\burndown\burndown.module on line 350 in Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher->dispatch() (line 89 of \core\lib\Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher.php).

When I go to the project board I can see the task

My drupal install

drupal 10.0.7
php 8.1.0
WAMP localhost install