Sounds like a call centre in the background. They ask "Am I speaking to.... " made up bogus name and when you tell them not to call again they hang up on you. The re route the numbers they are calling from and call about the same time every day. Most times I don't pick up but look the number up and if it's unsolicited call I block the number.

likely spam. called back and got "no routes found"

Left a hello, hello voice message and I could hear a call centre in the background. Either a scam or telemarketer