Motorola Photon 4G :: Deleted Messages Are Being Received Again

In a day, we receive many promotional messages. Usually, i dont like to keep these messages in my inbox. So, whenever i receive such messages, i will read those and delete immediately. But recently what i observed was if i read message and delete same from my inbox, after some time or so, again i will receive same message. I thought my service provider might be sending such messages so used to ignore those. But, recently, my friend sent me one message. I read that and deleted. To my surprise, after some time, i received same message. When inquired to my friend, found that he has sent that message one's only.