I'd been with Vodafone so long that when I switched to O2 I didn't even think about setting up my voicemail! I've tried to do it but it's still not cutting in when someone phones me.
I've tried dialling 1750 to activate voicemail but I get 3 beeps and the call cuts out. I tried 1760 as well and the same thing happened. All I've managed to do so far is change my PIN on 901 and get a message telling me I have no messages!
If anyone can help I'd be really grateful - I don't get loads of messages but it's nice to have it working!
