Having trouble getting hold of a seller.

Not sure if anyone has ever dealt with this, I've been using eBay (buying & occasionally selling for years). I purchased an item & stupidly forgot to measure properly. Low & behold the item won't work for my needs & the seller says items can be returned within 14 days.

OK great, I contacted the seller the day the item arrived & waited for a response.

The response: "I’m in cardiac rehabilitation right now."

It's now been 9 days & I haven't heard back. The account is still posting new items to be sold. It's one of those huge accounts with 140K items sold, so I'm assuming multiple people run this business, but whoever is running the messages for it is either seriously ill, or trying to avoid a return? I have no idea.

I contacted them again on the 7th, but like I said, I haven't heard back.

Should I keep waiting & messaging them or do I need to bring someone from eBay into this?

Thanks in advance!