Stop Veeam ONE Monitor and Veeam ONE Reporter services.
Open the registry and navigate to the HKEY_LOCAL_MACHINE\Software\Veeam\Veeam ONE Monitor\Service registry key.
Create a new entry with the following parameters or modify if exists:
Name: MaxTimeDiff
Type: DWORD
Value: the value that can cover the time difference in seconds
Start Veeam ONE Monitor and Veeam ONE Reporter services.
If you have any questions or problems, please contact Veeam Support at http://www.veeam.com/support