Can't receive call

[ANDYS01]

Hi all,
I have got Lumia 1020, people can not call me, said I have switch off my phone,
it happens from I have got it Amber firmware until now Cyan + GDR1, I don't have much calls, but I know it has happened around 5 times since I bought it about 1 year now, and I realised when people complain they can't reach me.
It happen to my friend Lumia 1020 as well but maybe 2 times and 1 year old as well.
I am on 2G 99% of the time, can't figure out what is the problem.
Can any one help
Thanks

 

[jeetu4444]

Its your network provider tat is the problem not your phone

 

[ANDYS01]

Its your network provider tat is the problem not your phone

At the same time same place same carrier my friend Lumia 1020 was trying to call me when just about to go home and sit inside of my car. After restart work fine, other time I lost my connection I didn't know until friends tell me and didn't do anything then it back to normal, its quite hard to explain, I don't use my phone often as standby roughly 6 days 1 full charge so don't know when or how often it happening like that. So I am start to wondering either its Nokia hardware or MS OS ?! Or any setting I could do to avoid that? Thanks