Is there something wrong with the Community Total count on the event update screen? At 15 Days 2Hr 37 min the total shows 95,772,638 roses. It took about three days for the community to collect the first 80,000 roses required for the first community prize. If the total is correct, then in almost three days, since then the community has only collected 15,779,983 roses. It seems very unlikely that the collection rate would drop so dramatically.
I doubt it matters what device you are on but I use an IPAD mini IOS 8.1.3 and I am running version 1.4.2 of Fantasy Forest Story.