I have gotten many items for collections that won't go into the collections; the items are not locked..

I have gotten many items for collections that won't go into the collections; the items are not locked (higher lvl items) and are for current donatable items. For example, Wool Mittens - it shows it can be donated into the collection (no lock on it) and I have that item, but it won't allow it to be donated. When I go to the item it shows it's collection item, but not green "!" and cannot be selected to add to collection. Does the item have to match the same stats of that the collection shows? It seems some didn't it just had to have the same name not same stats?