Automated message saying my router has an issue. No ID. Didn't call back

phoned twice with no message. Suspect Spam/physing

Caller: Recorded message pertaining to be from Telstra.

Message by a female with indian accent states: 'We are contacting you to inform you that the modem we supplied to you is faulty. Please press 1 to speak to our technician so we can repair or replace the item.' I just hung up. Have had similar calls from other (03) numbers using the same tactics. It is just a scam call.

Call telling me I need to upgrade internet modem. Told me to call the number. I didn’t