If the uninstallation was no good, the problem needs to he handled in a different way. Firstly, open the application and create 2 entries with different names. After this process, attempt to save or edit one entry. If it works, then it means the database with entries is corrupted and you will have to re-add them. Additionally, to make it easier, export the big database to another format, then close it and open it again. Load the database and edit/save the entries. It should work this time.