Noob question about sunder charms

I have a sunder charm for lightning resistance in my inventory. If I keep running terror zones will another lightning sunder drop if I have it in my inventory? I tried looking for this info online but can't find it anywhere. Chatgpt tells me it is one type of sunder per character and another won't drop unless I move it out of my character so I moved it to my mule but it is making terror zones a pain now. I want another for my lightning sorc. Some concrete info would be appreciated thanks.