Silly for them not to agree to cancel for you to receive your money back, all you can do now is to wait for one day to pass the item's last estimated date for delivery and proceed this way:
Go right of the item purchased, and from More Actions select.... I Have Not Received My Item.
If you are not fully refunded within 3 days, you must escalate the case on day 4 or within 30 days from opening the case, and eBay will step in and force the refund.
Do not close the case early for any excuse or promise the seller may give, and do not forget to escalate.
Do not worry your money is safe, just follow the above, you just need to have a bit of a wait to receive it.
@many-mini-parts