Robocall - nobody on other end. Called back, straight to hold music

Called but did not leave message.

Claimed to be ACF (Australian Conservation Foundation) after my having donated to the organisation directly recently; wnet through currrent agendas, which of the main areas of concern I am focusing on that was part of a donation associated survey; asked for donation, monthly payment donation, asked if I am still at my address, and articulated my email address. I checked with ACF directly - the organisation does use third party, but number is not tethered with a company ID, so not being a listed caller, I'd recommend going direct to legitimate ACF site and contact directly if you receive such a call and are interested - but ask what organisation they are also.

Long silence then as I put the phone down a voice addressed me by name. I didn't wait to talk and they didn't call back.

Robocall

Keeps ringing me & hanging up

who called me

Caller: No idea

Voicemail asked for me by name but they thought I had answered the call, no actual message was left. Called back and straight to hold music