After deleting the backup from disk (from the Veeam BR console), the backup task works well.
Here it is the support answer:
1. From the Veeam Backup & Replication console, locate the backup files from the Backup & Replication view > disk. Then right click the EP restore points and click remove from disk.
2. Point the Endpoint backup job to a new location or a new repository. This will create a new chain on this new repo.
3. Clear out the Veeam Endpoint Backup database from which the job will need to be reconfigured and the backups will create a new chain and new vbm file. This can be done by the following:
1. Open up RegEdit
2. Look for HKEY_LOCAL_MACHINE\SOFTWARE\Veeam\Veeam Endpoint
3. Create new DWORD value called ReCreateDatabase and assign to it 1 (decimal)
4. Start Endpoint service manually or just reboot your pc.
5. If Endpoint started successfully, delete created key.