Sheets are being added to the index automatically, even though they have been deleted.
If your sheet numbers are auto-appearing or not deleting, it is typically due to the Sheet Set integration. An important Land F/X feature is the automatic linking with AutoCAD Sheet Set data for the sheet number. It can still misfire at times, as you have multiple options for creating and numbering a sheet using sheet sets.
You should be able to change the number through the Sheet Set interface first. Our Project Manager will then read the changed number correctly.
For more information, see our Working With Sheet Sets page.