Why I could not read the other sms's except the first SMS?
It looks like RcvdEnd never gets reset back to zero because RcvdConf is set to zero when RcvdEnd is 2, which means it will never get to 3 and reset it (at least not when you are expecting it to). I'm not sure how many new lines you are supposed to be checking for but the way it is set up now or is looking for two on the first message, and three for every message thereafter. You might want to rework the logic and maybe move where that value gets reset.