how to access voicemail with o2
1) Dial your own number. 2) Press *. 3) Enter your pin â When prompted enter your pin or passcode. This is same pin you use when accessing your voicemail from your own phone. If you do not know your pin and you are a Callmaster Mobile customer, please do get in touch with us, we can request a pin re-set for you.4) Listen to your messages.) Press *. 3) Enter your pin â When prompted enter your pin or passcode. This is same pin you use when accessing your voicemail from your own phone. If you do not know your pin and you are a Callmaster Mobile customer, please do get in touch with us, we can request a pin re-set for you.