Yepme — unwanted sms

One day i ordered one product from yepme...after that day, it is sent messages daily on my no [protected] from yepme...I tried many times to stop but it couldn't be stopped by yepme...for stopping i sent many messages having written YSTOP and sent to 56161...I was not aware of this chargeable message...and i sent last message which is not sent because of insufficient balance...then i got...sms YSTOP to 56161 is chargeable...please help me for stopping these messages on my no [protected] from yepme... ... Following are some messages of last few days which is sent on my no by yepme :- . On[protected], at 12:09 pm Buy 1 Get 1 Free on our Best-seller Men shoes. Hurry, limited stock. Visit: http://bit.ly/1AOfpU9 Optout sms YSTOP to[protected][protected][protected] On[protected], at 8:00 pm #Stunning 499! - Shop for Apparels @ 499 & below. Buy Now! Visit: http://bit.ly/1EqIEwY Optout sms YSTOP to[protected][protected][protected] On[protected], at 7:38 pm Super Friday - Buy 3 T-Shirts @ 499 only. Valid for 3 hours. Shop Now! Visit: http://bit.ly/1cv2XDw Optout sms YSTOP to 56161