MORE than highly suspicious.  Scammer for sure.    I listened to a recording (woman's voice) about the urgency of lowering my credit card rate after (they claim) "several attempts to contact me".  They disconnected when I didn't respond immediately.
1.  That is the first call ever.
2. They didn't mention "which" credit card. A legit credit card company is going to let you know who they represent.

Are we in agreement that the amount of robotic scams have drastically increased in the past few months? Ah the bane of living in a techno-world.