Is it safe or not to take flovent and advair together?

Yes . The steroid in flovent, fluticasone, is already in advair, so adding Flovent to advair might give you really high doses of fluticasone, depending on the dosage of the inhalers. Very high doses of inhaled steroids can cause some side effects with long term use, but are fine in the short run. Apart from that there shouldn't be a problem.