They had to stop it because of , er, well, er….ISIS..
Nah, they just renamed the agency.* No mention of it from series 6 onwards.
The most amusing thing, was they had a ton of merchandise with the ISIS logo on it, which had to get skipped.
“I was at a meeting with the FX execs and I said, ‘You know, with all this extra ISIS merchandise, you should just make the bad guys buy it.’ Dead silence. And then they said, ‘We have a lot of ISIS merchandise.’ So I guess that’s all going to a landfill somewhere.”
– Adam Reed (Creator)
*Well it’s a bit more complicated than that, but don’t want to post spoilers to all the funky uncles who are playing catchup.