This report claims it didn't happen since the 1800s.. it also did not kccur, the Catholic claim goes, when Benedict visited in 2007..
From the Catholic Herald report:
The blood of St Januarius liquefied in the presence of a pope for the first time since 1848 on Saturday.
The blood of the patron saint of Naples, which is normally solid, partially liquefied after Pope Francis kissed the relic during his day trip to the southern Italian city.
FRANCIS ALSO SAID TO SPREAD THE WORLD OF THE EVENT.. the Internet is, with lots of skeptics and doubters raising eyebrows and disagreeable conclusions to the liquidification claims..