ask alex gardiner how to test resin in a glass of water, this is what you should do first, it will tell you if your resin is ok but cant remember exactly how to do it once you have eliminated this as a problem, look at the tds coming out of the ro, as long as that is ok then check the di.
sounds like crap resin to me, if you just bought it from purefreedom which i bet you did just like me, have noticed that the tulision that i got from them last week is crap mate, i will be going to adaqua in future, everyone recons they are good.
also for the same price or cheaper gardiners sell you 5kg in a cool sealable tub