Caller: O V or O B then something unintelligible

Unsolicited call. Potentially Phishing. Calling from O V or O B then something unintelligible to check if I am aware of recent Government changes to energy pricing. When I asked again who was calling (I couldn't understand her first or second time) I was advised they are not a retailer but similar to I select. **Searching on the internet I cannot find any comparison site the looks like O B or O V*.. They Just want to check my energy rates and make sure I am on the cheapest plan. I order to do this they will require personal information but have not advised me of this. I asked how they got my number and the response was from their data management team, Could not advise where the data mangement team got it. I am pretty sure I am on the do not call register. Asked caller to remove me from their call register. Between these energy calls and the spam / scammer calls allegedly from banks, ATO, Amazon etc,etc,etc I get 8-10 calls per week. I am very near the point where I will stop asking politely. I suspect this is a scammer trying to get information as when I call the number back it is "NOT IN SERVICE".