The bottom line is that they cannot sell you what they do not have. The issue of spare parts availability is universal these days -- there are many drivers whose cars are being declared total losses after accidents due to repair part unavailability despite relatively minor damage. Look around - there are likely alternate sources of batteries;  if you're in the US, try parts-people.com  
I have placed the order for Laptop batteries in Dell Online and the Laptops are not older than 4 yrs. But Dell not able to provide the batteries after taking the order. I waited more than a month the order status shows it’s already shipped. It’s same status in more than 20 days. I finally called to Dell order support team and they said they don’t have stock and we are not going to process the order and will refund the amount.  1) In that case they should not take the order. 2) why the order status show,  Ordered shipped in line track 3) Dell should support minimum 5 years when the product sell by them.  opinion? DELL-Admin>  That product is still under warranty. I know battery will not cover under warranty after 1 year, so I have order it in online.   Because of the batteries shortage, we kept our own Laptops ideal and brought  from venders rental basis for employs. We called Dell to inform to senior sales people this issues and they didn’t respond even after waited phone line more than1 hr. Please see the order tracking info below = 
Order shipped date Mar 24, 2022