This may be due to the following reasons
- Proxy/Firewall in the machines may block the communication to Freshservice. 
- If the asset limit is reached, new assets would reach to Trash folder within Inventory 
- If the asset was already scanned and identified in a different name with a different serial number then the updates would be reflected over the existing asset. 
Reach out to our support team at support@freshservice.com for any assistance on the same.
