Ok i've had enough of this so i'm gonna see if anyone has the same problems:

Lately (?last 2 weeks?) i've been sent TXTs (this FREE whocalled TXT ...) saying i've missed a call - but my phone was always turned on with full reception in urban christchurch!

 (this happens about 50% but then i dont get many calls - say a handful a week)

This morning something weirder happened i "missed a call" from a weird australian +6128507xxyy. ringing the number back was a "dead tone".

?