Your UE may be setup to only register on the CS domain (LOCATION AREA UPDATE).
All DL Power HSPA test cases require the UE to also register on the PS domain (GPRS ATTACH / ROUTING AREA UPDATE).
Verify that your UE is setup to perform a combined CS+PS attach. E.g. On any Nokia UE, you may have the option to set GPRS availability to 'when available' as opposed to 'when needed'.
Some UE's may only perform a PS Attach at the time when data call is setup. Please contact Spirent support in that case.
If you UE does not register on either domain (CS or PS), please follow some of the other FAQ articles or contact Spirent Support/