'You Missed a Call From Me' messages from O2

[DinoF]

This is seriously starting to get on my nerves...!!!! 

Every week (And I do mean EVERY week..!), at least once a week, I get these stupid 'You Missed a Call From Me' free texts from O2.

  WHY....?!?!?!?!?  My phone sits in front of my eyes on my desk, where I work, it does not ring, I have no diverts on and have full bars of service and yet I get this message to say 'You missed a call from me'...!??!!?  How can I miss a call when the phone didn't even ring in the first place...?!

Dialling back the number just gets an automated response which says, '.......the number you have dialled is incorrect, please try again'.  This makes NO sense...??

There are no messages in my voicemails to suggest I have 'missed a call' so why am I getting these EVERY WEEK...???

I have tried turning my voicemails off and on to see if it makes a difference but it doesn't. 

Is there any way I can turn these texts off with O2? If I have a missed call, my iPhone 5 will show me (via the Phone app in Notification Center) - I do NOT want to receive a 'free text' telling me as well (seeing that the texts are nearly always wrong)......!!

[MI5]

Some of these types of calls are scams that just want you to call them back at extortionate call rates....