Happens to me on like 30% of all my transactions a month. There was a time on Buyer Beware Kenya people used to condemn those that have sent money to a wrong number claiming that they ought to have used Hakikisha. I was always forced to rant on such posts informing people that the Hakikisha part fails at times. Be it at an Agent, Lipa na Mpesa, or sending to another customer.
At least nowadays, people don't refer to Hakikisha when posts of sending money to the wrong number shows up.
The Hakikisha thing ought to be integrated the way Equity Bank has done theirs. When the pop up shows, you have two options
1. Yes - to send money
2. No - to cancel transaction
So when the pop-up fails to appear, the transaction is automatically cancelled. Also, when you ignore the pop-up the transaction will not be processed. It is a must for you to select either of the two options. How I wish Hakikisha was that way.