you did receive it and thats the report, Sent means Kannel deliver the SMS to SMSC (configured in Kannel)
it will change to Deliver (p_status=3) when Kannel received appropriate report from SMSC that the SMS is received by receiver
If your question why playSMS did not report Delivered (blue dot on All sent messages menu) then its because playSMS did not receive the DLR with status Delivered from Kannel, and why Kannel did not report it its because Kannel did not received the report from SMSC. So why SMSC did not report Delivered when the SMS was delivered, this may be because there were no such report available on SMSC, or something was wrong either in SMSC or Kannel
anton