Setting the number of private messages to 0

When I set the number of messages for a new group designed to prevent the abuse of private messages for spam and illegal promotions, I started experiencing this error. It keeps occurring for users in the group that has the message limit set to 0.

TypeError: IPS\DateTime::ts(): Argument #1 ($timestamp) must be of type int, null given, called in applications/core/sources/Messenger/Conversation.php on line 211 (0)
#0 applications/core/sources/Messenger/Conversation.php(211): IPS\DateTime::ts(NULL)
#1 system/Content/Item.php(203): IPS\core\Messenger\Conversation::canCreate(Object(IPS\Member), NULL, true)
#2 applications/core/modules/front/messaging/messenger.php(540): IPS\Content\Item::create()
#3 system/Dispatcher/Controller.php(128): IPS\core\modules\front\messaging\messenger->compose()
#4 system/Content/Controller.php(124): IPS\Dispatcher\Controller->execute()
#5 applications/core/modules/front/messaging/messenger.php(97): IPS\Content\Controller->execute()
#6 system/Dispatcher/Dispatcher.php(169): IPS\core\modules\front\messaging\messenger->execute()
#7 index.php(16): IPS\Dispatcher->run()
#8 {main}

#0 init.php(827): IPS\Log::log('TypeError: IPS\\...', 'uncaught_except...')
#1 [internal function]: IPS\IPS::exceptionHandler(Object(TypeError))
#2 {main}