I returned a call from (02) 9171 7929 but the voicemail didn't mention the company name

I let the call ring out. I received a voicemail and when I listed to it, it was background noise which sounded like a call centre. Possible foreign language(?). I then called the number which went to a generic voicemail saying that the person at extension 91717929 was unavailable. Usually a telemarketer will have a voice recording to say you've missed a call from .... charity etc. Which makes me think this call could be a scammer.