Hi Pavan,
We have been having the same issue (and other similar) since we started using the product and not having any luck finding a fix.
Recordings work fine, playing the transaction in the recorder works fine, testing works fine, but eventually the transactions start intermittently failing. Have tried moving the transactions to different players and some work fine for a while and then start playing up, others start playing up straight away, there doesn't seem any pattern to it, apart from the fact it is only some transactions that do it.
Will be good to see if you find any resolution to this.
I have my fingers crossed that the next update that has been announced may help fix some of these issues.