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MagentoFrameworkConfigDomValidationException: Element ‘argument’: Duplicate key-sequence

I have an error when the developer-mode is active.
The Exception is thrown out when entering any product detail page.
I am running magento 2.3.4
could you please help finding a solution

1 exception(s):

Exception #0 (MagentoFrameworkConfigDomValidationException): Element ‘argument’: Duplicate key-sequence [‘title’] in key identity-constraint ‘blockArgumentName’.
Line: 1388

Exception #0 (MagentoFrameworkConfigDomValidationException): Element ‘argument’: Duplicate key-sequence [‘title’] in key identity-constraint ‘blockArgumentName’.
Line: 1388

#1 MagentoFrameworkConfigDom->__construct() called at [vendor/magento/framework/ObjectManager/Factory/AbstractFactory.php:121]
#2 MagentoFrameworkObjectManagerFactoryAbstractFactory->createObject() called at [vendor/magento/framework/ObjectManager/Factory/Compiled.php:108]
#3 MagentoFrameworkObjectManagerFactoryCompiled->create() called at [vendor/magento/framework/ObjectManager/ObjectManager.php:56]
#4 MagentoFrameworkObjectManagerObjectManager->create() called at [vendor/magento/framework/Config/DomFactory.php:43]
#5 MagentoFrameworkConfigDomFactory->createDom() called at [vendor/magento/framework/View/Model/Layout/Update/Validator.php:141]
#6 MagentoFrameworkViewModelLayoutUpdateValidator->isValid() called at [vendor/magento/framework/View/Model/Layout/Merge.php:512]
#7 MagentoFrameworkViewModelLayoutMerge->_validateMergedLayout() called at [vendor/magento/framework/View/Model/Layout/Merge.php:488]
#8 MagentoFrameworkViewModelLayoutMerge->load() called at [generated/code/Magento/Framework/View/Model/Layout/Merge/Interceptor.php:206]
#9 MagentoFrameworkViewModelLayoutMergeInterceptor->load() called at [vendor/magento/framework/View/Layout/Builder.php:86]
#10 MagentoFrameworkViewLayoutBuilder->loadLayoutUpdates() called at [vendor/magento/framework/View/Layout/Builder.php:63]
#11 MagentoFrameworkViewLayoutBuilder->build() called at [vendor/magento/framework/View/Layout.php:257]
#12 MagentoFrameworkViewLayout->build() called at [vendor/magento/framework/View/Layout.php:882]
#13 MagentoFrameworkViewLayout->getBlock() called at [generated/code/Magento/Framework/View/Layout/Interceptor.php:414]
#14 MagentoFrameworkViewLayoutInterceptor->getBlock() called at [vendor/magento/module-cms/Helper/Page.php:215]
#15 MagentoCmsHelperPage->prepareResultPage() called at [vendor/magento/module-cms/Controller/Noroute/Index.php:47]
#16 MagentoCmsControllerNorouteIndex->execute() called at [generated/code/Magento/Cms/Controller/Noroute/Index/Interceptor.php:24]
#17 MagentoCmsControllerNorouteIndexInterceptor->execute() called at [vendor/magento/framework/App/Action/Action.php:108]
#18 MagentoFrameworkAppActionAction->dispatch() called at [vendor/magento/framework/Interception/Interceptor.php:58]
#19 MagentoCmsControllerNorouteIndexInterceptor->___callParent() called at [vendor/magento/framework/Interception/Interceptor.php:138]
#20 MagentoCmsControllerNorouteIndexInterceptor->MagentoFrameworkInterception{closure}() called at [vendor/magento/framework/Interception/Interceptor.php:153]
#21 MagentoCmsControllerNorouteIndexInterceptor->___callPlugins() called at [generated/code/Magento/Cms/Controller/Noroute/Index/Interceptor.php:39]
#22 MagentoCmsControllerNorouteIndexInterceptor->dispatch() called at [vendor/magento/framework/App/FrontController.php:159]
#23 MagentoFrameworkAppFrontController->processRequest() called at [vendor/magento/framework/App/FrontController.php:98]
#24 MagentoFrameworkAppFrontController->dispatch() called at [vendor/magento/framework/Interception/Interceptor.php:58]
#25 MagentoFrameworkAppFrontControllerInterceptor->___callParent() called at [vendor/magento/framework/Interception/Interceptor.php:138]
#26 MagentoFrameworkAppFrontControllerInterceptor->MagentoFrameworkInterception{closure}() called at [vendor/magento/module-store/App/FrontController/Plugin/RequestPreprocessor.php:99]
#27 MagentoStoreAppFrontControllerPluginRequestPreprocessor->aroundDispatch() called at [vendor/magento/framework/Interception/Interceptor.php:135]
#28 MagentoFrameworkAppFrontControllerInterceptor->MagentoFrameworkInterception{closure}() called at [vendor/magento/module-page-cache/Model/App/FrontController/BuiltinPlugin.php:73]
#29 MagentoPageCacheModelAppFrontControllerBuiltinPlugin->aroundDispatch() called at [vendor/magento/framework/Interception/Interceptor.php:135]
#30 MagentoFrameworkAppFrontControllerInterceptor->MagentoFrameworkInterception{closure}() called at [vendor/magento/framework/Interception/Interceptor.php:153]
#31 MagentoFrameworkAppFrontControllerInterceptor->___callPlugins() called at [generated/code/Magento/Framework/App/FrontController/Interceptor.php:26]
#32 MagentoFrameworkAppFrontControllerInterceptor->dispatch() called at [vendor/magento/framework/App/Http.php:116]
#33 MagentoFrameworkAppHttp->launch() called at [vendor/magento/framework/App/Bootstrap.php:261]
#34 MagentoFrameworkAppBootstrap->run() called at [pub/index.php:40]

Thanks in advance!