Callers number is not given in Voicemail

Since joining Smarty my daughter has rung me several times.  The phone sometimes goes straight to voicemail without ringing at all.  If she leaves me a voicemail I get a text telling me I have a message but when I play it it does not give me her number.,  She recently left me a voicemail when she was ill and as it didn't sound like her I had no idea who the message was from!

She is in my contacts, as a favourite, but I had no idea she had called me....Any ideas?  I never had this with my previous carrier.