Calls routing to other sites

I have a 5 site Asterix set-up, calls destined for site A are ringing at SIte B. What could cause this to happen? I did not configure this system but I have reviewed it in some detail. Is there somewhere in particular in FreePBX I should check. There may have been configured some sort of site roll-over in case nobody answers at Site A to ring site B. I have checked all the ring groups and queues and they have the correct instructions in case of no answer.
Thanks

We’re going to need lots more information, but the place I’d start looking is in the outbound trunk configuration. That is where you decide, based on dialing rules, how to get a call from point A to point B.

I have 1 dialing rule and that is 9, and that sends everything to the same trunk(ZAP Channel G0) and there is nothing special about that configuration. This is really becoming a problem. Anywhere I can look to try and sort this out?
Thanks,