The amount of fillers which made Naruto's look small and how badly placed they were, plus a lot of the fillers themselves were terrible. Add that to waning interest, it just didn't make as much as it did.
Studio Pierrot said it was cancelled, not that it's on hiatus. Lots of unsubstantiated rumours have been circulating on the internet though.
After Ichigo vs Aizen, the filler was atrocious and Fullbring arc was weak so popularity tanked which led to cancellation, it might start after this arc but that is pure speculation.Wow bleach got cancelled...... that sucks lol It's such an epic anime loved Ichigo vs aizen