I bought a pair of sandals for my wedding in July. The sandals have 1 1/2 in heels since I have bad knees and am not supposed to wear heels at all. The problem I found is 1. my feet are wider than the sandal and 2. my feet slide forward in the heel when they start to sweat. Is there anything I can do to stop them from sliding? I think I would make it through the ceremony if I could at least get my feet to stay in the right spot.