Suggest Treatment For Light Bleeding After Using Implanon

I received an Implanon implant about four and a half months ago. A week after the implant, I began bleeding. Since then, the bleeding has not stopped (except for a one-week window about two months ago). The bleeding is lighter than a normal period for me, but I still must use tampons at ALL times. I called the clinic and they say this is normal, but there must be something I can do...