I've been treating this jock itch at the moment, but it seems it is not working anymore. I successfully treated it before, however I think I need stronger solution, AND is there any other skin problem aside from this?
If the clotrimazole isn't working- you should go to your doctor to get something stronger (possibly an oral medication) and to be sure that it's not another issue causing the symptoms you are seeing (for example psoriasis can present similar symptoms). Also, jock itch can be caused by yeast or bacteria so it's good to be able to tell which one is causing yours and treat it accordingly.
You also want to make sure that you are keeping the area clean and it may also help to make sure you are wearing lose fitting clothing.