How to fix an error when migrating a virtual machine?

Question

Hyper-V

Good afternoon!
There is an MS cluster of two hyper-v server 2012r2 nodes and storage for them on win2012r2.
Previously, the cluster virtual machines were located on the SMB3 file share of the win2012r2 server.
Now there is a desire to connect another storage device to the cluster using the iscsi protocol.
Connected, made a clustered CSV volume and connected to hyper-v nodes.
When creating a virtual machine, everything is fine. But the cluster does not want to migrate existing ones from SMB3 to CSV and gives an access error.
In which direction to dig to solve the problem?