The most common reason a property is being liquidated upon first death is that its sale event is linked to a client's mortality event.
To check this, navigate to the property in question on the dashboard and open the entry.
Once the property is open navigate to the timing section and check the sell event listed.
If you see the property sell event is linked to the first spouse's death this is easily fixed.
1. Select the plan end icon
2. Set as an end event
3. Click Done to save