A Refurbished product is literally "A defective/broken product returned by the customer and brought back to manufacture settings and standards through testing, verification and repair(s)".
I personally rarely buy any refurbished products and HDDs is not one of them! I can guarantee you refurbished products on average has a higher failure rate than retail, how much higher? that's anyone's guess. Certain products such as HDDs and SSDs can have unpredictable lifespans, it's unlikely but it happens - they can last 5 minutes to 5 years. The fact it's refurbished definitely isn't helping your cause, I would contact customer service and politely pester them to get that resolved. Better to invest an hour on the phone with customer service than risking a higher likelihood of losing your data.
PS: I need more coffee!
PSS: I'm not sharing!