We did upgrade for one of the customer from SDL 8.5 to Sites 9.1 and we are having issues saving the component with keywords.
Keyword with title 'Country Region' does not exist in Category 'Country' Tridion.ContentManager.ContentManagement.Category.GetKeywordDataByTitle(String title) at Tridion.ContentManager.ContentManagement.Category.GetKeywordByTitle(String title) at Tridion.ContentManager.ContentManagement.Fields.ItemField.ReadFromElement(XmlNodeList fieldNodes) at XmlElement contentContainer, Nullable`1 synchronizeFlags, LoadFlags loadFlags) at