You get an error like: missing FROM-clause entry for table… when you try to access the dictionary tab or in general any random tab.
Such errors happen due to bad cache entries of the client console. Please do a hard cache reset and try again.
Documentation Link - https://experienceleague.adobe.com/docs/campaign-classic/using/getting-started/starting-with-adobe-campaign/faq/faq-campaign-config.html?lang=en