Calls going straight to voicemail with - number of minutes?

[DNACowboy]

Pay monthly Iphone 4S.

I've recently had a number of silent calls from a friend going straight to voicemail with the length of call in MINUS number of minutes....For example

-3.25

-5.34

etc

Any ideas as to what might be going on?

thanks in advance

[Cleoriff · Accepted solution]

Hi @DNACowboy 

It may be that you have to reset network settings :
Settings > General > Reset > Reset Network Settings.
Then switch your voicemail off by dialling 1760 and switch back on by dialling 1750.
Check by dialling your mobile from another phone.
A link to a similar issue here. It may well be worth a try.
http://community.o2.co.uk/t5/Apple-iOS-Devices-iPhone-iPad/iPhone-4s-Voicemail-Notification-issue-Pl...