A D string broke and when I tried to remove it from the bridge (no pins) to replace it, it would not pull out. I finally took a pair of needle nosed pliers and pulled the string out. I thought that would solve the problem, but it didn't, because when I tried to put the new string through the bridge hole, it wouldn't pass through. Something is stuck in the bridge hole, I don't know what or how. Any suggestions about how to clear the hole safely?