Based on my scenario, we have two Hyper-V host, both servers was running on Windows Server 2012 and clustered.
1. Access to the hyperv host machines.
2. Verify and check the original IP address settings on both servers.
3. Change the subnet mask from 255.255.255.0 to 255.255.254.0 at both servers.
4. On the Cluster Core Resources > network properties, remove old settings <Your IP Address>/24 and add new settings <Your IP Address>/23 with put the same virtual IP address.
5. Testing & done.
