Problems with getting SIM card to work

[DJHB]

I have recently ordered a new SIM card from O2 for a Samsung GT-E1200T phone (i.e. dumb phone), which is a replacement phone for the same make and model that I had before, but was getting a bit old and tired, having been knocked about a bit. Anyway, with advice of an O2 advisor, cancelled old SIM card, copied contacts on to new SIM card, inserted into replacement Samsung phone, and got new SIM card activated....or so I thought. When I use new phone, I get no signal and just a screen message saying "SIM restricted", so can't make any calls, even to O2 to find out what went wrong. 

Can anyone suggest how I might resolve this issue so I can have a working phone again.

Thanks in advance!

[madasaf1sh]

@DJHB 

Where did you buy the phone from, as it sounds like the phone is blocked, so it might be best to start with the retailer.

[Enlli]

SIM restricted on Samsung usually means the phone is network locked to another carrier than O2