Personal Statement on Gap Year

Hi, I'm on a gap year atm, having just left my previous university as I hated it, and was under performing. I was just wondering, in regards to my personal statement, I got all 5 of my uni offers last year so i figured i could just reuse it again, but i called up one of my unis that i'm applying to, to confirm this, and they said i have to mention that i have studied at another university before as well as all the things that i will be doing in my gap year. I have no idea what to write on this because i won't be doing that much other than working.

Also, how much should i write on this? Should I keep the majority of my previous personal statement the same and just add a few things on what i'm doing on my gap year? Do i have to mention why i'm taking a gap year as well?

Thanks