Sellers make all sorts of promises and as you have found out to your detriment, promises can be broken.
If a month has passed you are too late to do anything through eBay, and need to now, turn to your payment provider for help with your refund.
If you come across something similar in the future, listen to no excuses or promises from the seller, but follow eBay's 30 day MBG Money Back Guarantee, the policy is written on every listing, now found on the right hand side beneath Payment and postage details.
Open the relevant case, and escalate on day 4 if not refunded beforehand.