The application could not run because of the following error:

Type: Error
Message: Call to a member function keys() on null
File: /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/src/Application/Services/Placeholder/PlaceholderService.php
Line: 564

#0 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/src/Application/Services/Placeholder/PlaceholderService.php(124): AmeliaBookingApplicationServicesPlaceholderPlaceholderService->getCouponsData(Array, 0)
#1 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/src/Application/Services/Notification/EmailNotificationService.php(74): AmeliaBookingApplicationServicesPlaceholderPlaceholderService->getPlaceholdersData(Array, 0, '7324b96eed', 'email')
#2 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/src/Application/Services/Notification/AbstractNotificationService.php(467): AmeliaBookingApplicationServicesNotificationEmailNotificationService->sendNotification(Array, Object(AmeliaBookingDomainEntityNotificationNotification), true, 0)
#3 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/src/Application/Services/Notification/AbstractNotificationService.php(447): AmeliaBookingApplicationServicesNotificationAbstractNotificationService->sendBookingsNotifications(Object(AmeliaBookingDomainEntityNotificationNotification), Object(AmeliaBookingDomainCollectionCollection))
#4 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/src/Application/Commands/Notification/SendScheduledNotificationsCommandHandler.php(41): AmeliaBookingApplicationServicesNotificationAbstractNotificationService->sendFollowUpNotifications('appointment')
#5 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/vendor/league/tactician/src/Handler/CommandHandlerMiddleware.php(71): AmeliaBookingApplicationCommandsNotificationSendScheduledNotificationsCommandHandler->handle(Object(AmeliaBookingApplicationCommandsNotificationSendScheduledNotificationsCommand))
#6 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/vendor/league/tactician/src/CommandBus.php(62): LeagueTacticianHandlerCommandHandlerMiddleware->execute(Object(AmeliaBookingApplicationCommandsNotificationSendScheduledNotificationsCommand), Object(Closure))
#7 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/vendor/league/tactician/src/Plugins/LockingMiddleware.php(36): LeagueTacticianCommandBus->LeagueTactician{closure}(Object(AmeliaBookingApplicationCommandsNotificationSendScheduledNotificationsCommand))
#8 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/vendor/league/tactician/src/Plugins/LockingMiddleware.php(66): LeagueTacticianPluginsLockingMiddleware->LeagueTacticianPlugins{closure}()
#9 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/vendor/league/tactician/src/Plugins/LockingMiddleware.php(45): LeagueTacticianPluginsLockingMiddleware->executeQueuedJobs()
#10 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/vendor/league/tactician/src/CommandBus.php(62): LeagueTacticianPluginsLockingMiddleware->execute(Object(AmeliaBookingApplicationCommandsNotificationSendScheduledNotificationsCommand), Object(Closure))
#11 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/vendor/league/tactician/src/CommandBus.php(42): LeagueTacticianCommandBus->LeagueTactician{closure}(Object(AmeliaBookingApplicationCommandsNotificationSendScheduledNotificationsCommand))
#12 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/src/Application/Controller/Controller.php(107): LeagueTacticianCommandBus->handle(Object(AmeliaBookingApplicationCommandsNotificationSendScheduledNotificationsCommand))
#13 [internal function]: AmeliaBookingApplicationControllerController->__invoke(Object(SlimHttpRequest), Object(SlimHttpResponse), Array)
#14 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/vendor/slim/slim/Slim/Handlers/Strategies/RequestResponse.php(41): call_user_func(Array, Object(SlimHttpRequest), Object(SlimHttpResponse), Array)
#15 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/vendor/slim/slim/Slim/Route.php(356): SlimHandlersStrategiesRequestResponse->__invoke(Array, Object(SlimHttpRequest), Object(SlimHttpResponse), Array)
#16 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/vendor/slim/slim/Slim/MiddlewareAwareTrait.php(117): SlimRoute->__invoke(Object(SlimHttpRequest), Object(SlimHttpResponse))
#17 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/vendor/slim/slim/Slim/Route.php(334): SlimRoute->callMiddlewareStack(Object(SlimHttpRequest), Object(SlimHttpResponse))
#18 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/vendor/slim/slim/Slim/App.php(515): SlimRoute->run(Object(SlimHttpRequest), Object(SlimHttpResponse))
#19 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/vendor/slim/slim/Slim/MiddlewareAwareTrait.php(117): SlimApp->__invoke(Object(SlimHttpRequest), Object(SlimHttpResponse))
#20 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/vendor/slim/slim/Slim/App.php(405): SlimApp->callMiddlewareStack(Object(SlimHttpRequest), Object(SlimHttpResponse))
#21 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/vendor/slim/slim/Slim/App.php(313): SlimApp->process(Object(SlimHttpRequest), Object(SlimHttpResponse))
#22 /home/caal2618/public_html/magni/wp-content/plugins/ameliabooking/ameliabooking.php(151): SlimApp->run()
#23 /home/caal2618/public_html/magni/wp-includes/class-wp-hook.php(287): AmeliaBookingPlugin::wpAmeliaApiCall('')
#24 /home/caal2618/public_html/magni/wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters('', Array)
#25 /home/caal2618/public_html/magni/wp-includes/plugin.php(478): WP_Hook->do_action(Array)
#26 /home/caal2618/public_html/magni/wp-admin/admin-ajax.php(175): do_action('wp_ajax_wpameli...')
#27 {main}

The error is always present

Thanks