What kind of pool do you have? Do you have tiered disk pool in the array?
Here is a link to how you can take snapshots via the various interfaces. Logging into the controller using Storage Advisor Embedded is the easiest by far if you need to take a quick snap on a volume if you don't have Ops Center installed:https://knowledge.hitachivantara.com/Documents/Storage/VSP_G130_GF350_GF370_GF700_GF900/88-08-0x/System_Management_Using_Embedded_Interfaces/15_Managing_snapshots
Alternatively you can also use Hitachi Ops Center-Administrator and/or -Protector to accomplish the same.
Below you can read just about everything there is about the snapshot engine in SVOS along with the limitations:Thin Image User Guide
As per the guide
Thin Image pool or HDP pool can be used. However, the following pools cannot be specified:
■ The pool for which Hitachi Dynamic Tiering or active flash is enabled.
■ The pool used for Dynamic Provisioning for Mainframe.
■ The pool for which the Data Direct Mapping attribute is enabled.