Facebook friend bomber

I tried to send PM to group members by FFB for a CB product but after 22 messages FB displayed a warning that I am trying to send a URL and going very fast I have to slowdown so I stopped sending PM, is there any safe method for mass PMing through FFB

thanks for input

Check your settings tab in FFB. You may want to increase the delay between messages.

I had recently asked the help desk what delay etc should I use for adding friends etc and here is what they said. Not sure about the PM though. Open a ticket to the help desk.
send 40 requests/day no more

2-3 seconds for every request. It will help you.