I purchased multiple items from a seller here about a month ago. One of the 1 items had some issues and 1 is unusable. I supplied supporting evidence to seller. Seller offered replacement for problematic item and refund for the defective item. It has been a month since the replacement/refund offer...no tracking, no refund... Seller did mention it would take time for RMA replacement, but it has been 1.5 month from purchase, and 1 month since settlement agreement. Doesn't seem like a bad guy, just not sure how long I should wait before I should be concerned. What is the appropriate way to handle this?