Ringing detection

Hi i have a little problem. i want to put my mobile phone into a ring group.
when someone try to call my local extension i want my local phone and my mobile phone to ring. The mobile phone will ring throut my SIP provider.

The problem i got is as soon the number dial for my mobile phone, asterisk detect it as if it was already answered. so my local extension isn’t rigning.

exten => s,1,Dial(SIP/221&SIP/222&${trunk}/${mobile},20)

this is how i have done that, but as of now, the extension 221 et 222 are not ringing. only my mobile phone. is there anyone how can make me a macro or something like that for ring detection on my mobile phone? thanx i’m in canada if it matther!! thanx!