Time Machine completed a verification of your backups. To improve reliability, Time Machine must create a new backup for you.
Fix using the instructions: Fix Time Machine Sparsebundle NAS Based Backup Errors
[NOTE] Although the instructions above do indeed work to fix a TM backup, the problem has continued to occur where TM would report the corrupted data and I would have to fix it again every 2-3 weeks. It simply wasn’t worth the trouble so I switched back to my wired USB backup drive.