Certain tables in Medilink were designed to be sequential and never deleted from. Some of the logic in Medilink depends on that fact, and when rows are skipped or deleted (via error or manually outside of Medilink), then Medilink may behave in unintended ways.
Here is a tool which can find and fix these missing rows:
1. Backup your current database.
2. Ensure index counts correct, Tools Menu -> Update Table Indexes. Note you don't need to do a Table Rebuild (although it won't hurt).
3. Download https://www.medilink.com.au/FillMissingRows.zip
4. Unzip to a separate folder, i.e. C:\Medilink32bnt\Utilities\FillMissingRows
5. Run C:\Medilink32bnt\Utilities\FillMissingRows\FillMissingRows.exe
6. A finished message will appear on screen (or an error message if there was a problem).