I created a list that would be entered into tinyDB, but when the application was run and added data again, the data that had been saved was lost and what was saved was the newly entered data.
Please help me so that data can be added and the original data that has been entered into tinyDB is not lost after the application is closed
You need to recover the list stored under "menuName" tag, add/modified/remove the items you want over the list and then, store the list under the tag "menuName".
It helps to add suffixes like _list or 's' to tags and variable names to remind you that they should contain lists, and never any non-list value like ' '.
For the default TinyDB value of a list, return Create Empty List, not text blank.