In some rare cases, invoice numbers may be inadvertently reused due to database corruption. This causes various problems in Medilink with regards duplicating invoices and receipts, and even paying off those receipts and claiming.

There is a utility available here to fix:

This is an experimental utility - it has not undergone extensive testing at this stage. Please ensure you backup prior to running this utility, and please test a few known problematic invoices/receipts etc after running it. If they are still a problem, please inform Medilink and consider rolling back changes.

You may also have to manually fix the corrupted rows in the database (the utility cannot fix that sort of thing).