Unused Service Templates can't be deleted

I made a mistake and i only wanted to delete the Service Template. I clicked on the template and then on modify to delete this. Then i got an Error:

Uncaught Error: Call to a member function toString() on null in /usr/share/icingaweb2/modules/director/application/controllers/ServiceController.php:250
Stack trace:
#0 /usr/share/icingaweb2/modules/director/library/Director/Web/Controller/ObjectController.php(465): Icinga\Module\Director\Controllers\ServiceController->loadObject()
#1 /usr/share/icingaweb2/modules/director/library/Director/Web/Controller/ObjectController.php(89): Icinga\Module\Director\Web\Controller\ObjectController->loadOptionalObject()
#2 /usr/share/icingaweb2/modules/director/application/controllers/ServiceController.php(41): Icinga\Module\Director\Web\Controller\ObjectController->init()
#3 /usr/share/php/Icinga/Web/Controller/ActionController.php(152): Icinga\Module\Director\Controllers\ServiceController->init()
#4 /usr/share/php/Icinga/Web/Controller/Dispatcher.php(59): Icinga\Web\Controller\ActionController->__construct(Object(Icinga\Web\Request), Object(Icinga\Web\Response), Array)
#5 /usr/share/icingaweb2/library/vendor/Zend/Controll

#0 [internal function]: Icinga\Application\Web->Icinga\Application{closure}()
#1 {main}

Icinga Web 2 version: 2.6.2

Used modules and their versions:
|director|master|
|incubator|0.6.0|
|ipl|v0.5.0|
|monitoring|2.6.2|
|reactbundle|0.8.0|

Web browser used: Google Chrome

Icinga 2 version used (icinga2 --version): version: r2.10.3-1

PHP version used (php --version): PHP 7.3.29-1~deb10u1 (cli)

Server operating system and version: Debian GNU/ LINUX 10 (buster)

You don’t want to use the master version of director. Since you’re a little behind, you probably don’t want the latest either.

Easiest way I see out of this is to upgrade up Icingaweb2 and Director (and reliant packages) other than hunt for the right version of director that plays well with your versions of other packages such as IPL.