No Gaurentee..Messy Mopping

I recently (3 months ago) purchased the 2-1 floorwhiz mop, as i generally thought it would last a long time and at the same time i threw away my "old" mop...i used it and was all happy bought the correct cleaning products so that i could use this mop for a long time, to my surprise.. I have to mop so slow so that the cover does not come,the cover is stretched out and keeps falling off, so again back to my old ways I have to constantly put this "rag" back on because it just slips of- its basically worn out already- i am a big fan of this product and I'm considering buying another one but I am to scared that I will have to replace it again 3 months later- this is not helping me in anyway because it feels like I am doing it the same way as I previously did, bearing in mind that I have just renovated my home,I unfortunately cannot find my slip as I trusted that this would work for me---- NOT HAPPY AT ALLL..so do I go and waste money again, because they not cheap or should I just go back to using the OLD MOP...hope someone gets this and responds positively