Trying to access array offset on value of type bool

(1/1) ErrorException

Trying to access array offset on value of type bool

in Gallery.php line 40
at RegisterExceptionHandler->handleError()in Gallery.php line 40
at Gallery->generateGalleryMainItem()in Gallery.php line 74
at Gallery->setFields()in Gallery.php line 28
at Gallery->handle()in Gallery.php line 14
at Gallery->__construct()in FlexibileConverter.php line 72
at FlexibileConverter->fieldConvert()in FlexibileConverter.php line 52
at FlexibileConverter->convertFields()in FlexibileConverter.php line 35
at FlexibileConverter->convert()in SingleContentService.php line 37
at SingleContentService->getSections()in ContentBaseService.php line 35
at ContentBaseService->processFields()in SingleContentService.php line 15
at SingleContentService->__construct()in ObjectCreator.php line 143
at ObjectCreator->createInstance()in ObjectCreator.php line 71
at ObjectCreator->resolve()in ResolverDispatcher.php line 71
at ResolverDispatcher->resolve()in Container.php line 390
at Container->resolveDefinition()in Container.php line 199
at Container->make()in Application.php line 127
at Application->get()in TypeHintContainerResolver.php line 59
at TypeHintContainerResolver->getParameters()in ResolverChain.php line 31
at ResolverChain->getParameters()in Invoker.php line 58
at Invoker->call()in WordPressControllersServiceProvider.php line 87
at WordPressControllersServiceProvider->Rareloop\Lumberjack\Providers\{closure}()in Dispatcher.php line 114
at Dispatcher->mindplay\middleman\{closure}()
at call_user_func()in Delegate.php line 38
at Delegate->handle()in Dispatcher.php line 59
at Dispatcher->handle()in Dispatcher.php line 75
at Dispatcher->dispatch()in WordPressControllersServiceProvider.php line 92
at WordPressControllersServiceProvider->handleRequest()in WordPressControllersServiceProvider.php line 35
at WordPressControllersServiceProvider->handleTemplateInclude()in class-wp-hook.php line 324
at WP_Hook->apply_filters()in plugin.php line 205
at apply_filters()in template-loader.php line 104
at require_once('/home/rjp/domains/nowyrjp.pan.pl/public_html/web/wp/wp-includes/template-loader.php')in wp-blog-header.php line 19
at require('/home/rjp/domains/nowyrjp.pan.pl/public_html/web/wp/wp-blog-header.php')in index.php line 7