Lmtd Basic Converter Equipment Charge

Starting last month a new charge for $8.85 per month for "Lmtd Basic Converter" has appeared on my billing invoice. It indicates further that this piece of equipment is inactive & should be returned. I have no idea what this equipment is nor why I am now being charged for it. This charged appeared again during the current billing cycle. Others have reported this same issue here in the form & have been instructed to Direct Message  Xfinity support using the icon at the top of the page, which I don't see. After further research I learned that I can't use the direct message feature until I've made my 1st post. So here it is. Thank you!