My twitterfeed update too often and I can't slow it down!

Why doesn't my twitterfeed update when I expect it to. I used a feed from EzineArticles to put put some content on my tweet. I used an update every hour. I have subsequently changed that to every 12 hours then 24 hours and still seem to be swamped with updates every 1-2 hours. I have de-activated for the time being but would like - say 1 or 2 updates each day.