Called--didn't leave a message

They ask to get permission to record the call,with out proper identification,I ask several times,what's the purpose of this call,they didn't reveal the reason or the name.

I never answer calls from unknown numbers. Didn't this time either. My solution? If you've got Metro PCS & an android, Metro Block-It works very well, & you can report them.
Also, the National Do Not Call Registry. Not only can you report the annoying number, but you can submit a complaint, with any details you may know, even if the call came from an unknown caller.

I called it back and they answer with "customer service how can I help you" they don't even say the name of the business

didnt leave a message and they do not identify themselves or company number belongs to.